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1.
ACS Nano ; 18(3): 2006-2016, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38205954

ABSTRACT

Light-driven microrobots capable of moving rapidly on water surfaces in response to external stimuli are widely used in a variety of fields, such as drug delivery, remote sampling, and biosensors. However, most light-driven microrobots use graphene and carbon nanotubes as photothermal materials, resulting in poor biocompatibility and degradability, which greatly limits their practical bioapplications. To address this challenge, a composition and microstructure design strategy with excellent photothermal properties suitable for the fabrication of light-driven microrobots was proposed in this work. The Mg-based metallic glass nanowires (Mg-MGNWs) were embedded with polyhydroxyalkanoates (PHA) to fabricate biocompatible and degradable microrobots with excellent photothermal effect and complex shapes. Consequently, the microrobot can be precisely driven by a near-infrared laser to achieve high efficiency and remote manipulation on the water surface for a long period of time, with a velocity of 9.91 mm/s at a power density of 2.0 W/cm2. Due to the Marangoni effect, programmable and complex motions of the microrobot such as linear, clockwise, counterclockwise, and obstacle avoidance motions can be achieved. The biocompatible and degradable microrobot fabrication strategy could have great potential in the fields of environmental detection, targeted drug delivery, disease diagnosis, and detection.


Subject(s)
Nanotubes, Carbon , Nanowires , Drug Delivery Systems , Glass , Water
3.
Burns ; 49(8): 2007-2017, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37407394

ABSTRACT

BACKGROUND: Aberrant biofunction of circular RNAs (circRNAs) is potently implicated in keloid formation. However, their roles have been underinvestigated. Recent evidence has demonstrated the pro-tumor role of circ_0000129 in cancers, and yet its role in keloid remains elusive. METHODS: RT-qPCR analysis and or western blotting of miR-485-3p, circ_0000129, and SGMS2 in keloid tissues and keloid fibroblasts was implemented. CCK8, EdU, scratch wound healing, and Transwell migration assays were perfomed to determine the keloid fibroblast proliferation and migration. Luciferase reporter and RIP assays were adopted to analyze the interaction among circ_0000129, miR-485-3p and SGMS2. RESULTS: In keloid tissues and keloid fibroblasts, circ_0000129 and SGMS2 were amplified, although miR-485-3p expression was downregulated. Furthermore, siRNAs-targeting endogenous circ_0000129 resulted in proliferation and migration defect of keloid fibroblasts. MiR-485-3p was simultaneously recognized by circ_0000129 and SGMS2 3'UTR. Rescued functional assays also illustrated that miR-485-3p loss was beneficial to the proliferation and migration of keloid fibroblasts, and these promoting changes were nullified by accompanied silence circ_0000129 or SGMS2. CONCLUSION: Circ_0000129 sponges miR-485-3p and releases expression of SGMS2 from the miR-485-3p suppression, promoting migration and proliferation of keloid fibroblasts, suggesting targeting circ_0000129/miR-485-3p/SGMS2 might be a promising strategy against keloid fibroblasts. AVAILABILITY OF DATA AND MATERIAL: All data generated or analyzed during this study are included in this article.


Subject(s)
Keloid , RNA, Circular , Humans , Cell Proliferation/genetics , Fibroblasts , Keloid/genetics , MicroRNAs/genetics , RNA, Circular/metabolism , Signal Transduction
4.
Nanoscale ; 15(14): 6802-6811, 2023 Apr 06.
Article in English | MEDLINE | ID: mdl-36951672

ABSTRACT

Oxygen reduction reaction (ORR) plays a crucial role in electrochemical energy conversion and storage devices such as metal-air batteries and water electrolyzers. Herein, a hierarchical nanoporous platinum-based metallic glass (NPMG) was developed by a facile fabrication method by dissolving in a liquid. The surface topography of the sample can be easily modulated by controlling the particle size of sodium chloride. As a result, the NPMG was proved to be efficient and robust as the ORR catalysts with super hydrophilicity and self-renewal capacity. The half-wave potential of the platinum-based porous material was 835 mV at 0.1 M KOH, even higher than that of the commercial Pt/C catalyst (823 mV) and the previously reported platinum material. In particular, platinum-based porous materials have extremely long stability (more than 500 h) through the self-renewal surface, which perfectly meets the requirements of catalyst stability in batteries. Our study has a better inspiration for developing and applying novel catalysts to prepare metal-air batteries.

5.
Plant Cell Rep ; 40(4): 691-705, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33559721

ABSTRACT

KEY MESSAGE: Endogenous hydrogen peroxide (H2O2) is involved in regulating the gibberellic acid-induced programmed cell death (PCD) of the aleurone layers by cooperating with OsVPE3 during rice seed germination. Preliminary experiments revealed that H2O2 produced by the NOX pathway is the key factor affecting rice germination. Histochemical analysis indicated that H2O2 is located in the aleurone layer. Both the H2O2 scavenger DMTU and the NOX inhibitor DPI decreased H2O2 content and significantly slowed down vacuolation in a dose-dependent manner. Interestingly, DMTU down-regulated the OsNOX8 transcript or DMTU and DPI decreased the intracellular H2O2 level, resulting in a delay of PCD. In contrast, GA and H2O2 up-regulated the OsNOX8 transcript and intracellular H2O2 level, leading to premature PCD, and the effects of GA and H2O2 were reversed by DMTU and DPI, respectively. These results showed that the imbalance of intracellular H2O2 levels leads to the delayed or premature PCD. Further experiments indicated that GA up-regulated the OsVPE3 transcript and VPE activity, and the effect was reversed by DPI. Furthermore, Ac-YVAD-CMK significantly blocked H2O2 accumulation, and DPI + Ac-YVAD-CMK had a more significant inhibitory effect compared with DPI alone, resulting in the delayed PCD, suggesting that OsVPE3 regulates PCD by promoting H2O2 generation. Meanwhile, DPI significantly inhibited the OsVPE3 transcript and VPE activity, and in turn delayed PCD occurrence, suggesting that the H2O2 produced by the NOX pathway may regulate PCD by up-regulating the OsVPE3 transcript. Thus, the endogenous H2O2 produced by the NOX pathway mediates the GA-induced PCD of rice aleurone layers by interacting with OsVPE3.


Subject(s)
Gibberellins/metabolism , Hydrogen Peroxide/metabolism , Oryza/cytology , Oryza/metabolism , Plant Proteins/metabolism , Apoptosis , Gene Expression Regulation, Plant , Germination/drug effects , Germination/physiology , Gibberellins/pharmacology , Hydrogen Peroxide/pharmacology , Oryza/drug effects , Plant Cells/metabolism , Plant Proteins/genetics , Seeds/cytology , Seeds/drug effects , Seeds/metabolism , Thiourea/analogs & derivatives , Thiourea/pharmacology , Vacuoles/metabolism
6.
Rice (N Y) ; 13(1): 22, 2020 Mar 30.
Article in English | MEDLINE | ID: mdl-32232682

ABSTRACT

BACKGROUND: Vacuolar processing enzymes (VPEs) have been identified as the enzymes that regulate vacuole-mediated programmed cell death (PCD) in plants. The mechanism that VPE regulates the PCD in rice aleurone layers remains unknown. RESULTS: The aleurone layers treated with distilled water exerted caspase-1 and VPE activity, both of which were inhibited by the caspase-1 specific inhibitor Ac-YVAD-CMK but not by the caspase-3 specific inhibitor Ac-DEVD-CHO. However, the caspase-1 and caspase-3 inhibitors weakened the activity of caspase-3. Combined with the effects of endogenous gibberellin (GA) on the induction of OsVPEs, we suggest that the OsVPE3 in the aleurone layers, which exhibits caspase-1-like activity, is a key molecule in GA-induced PCD via regulating the protease with caspase-3-like activity. Many studies have confirmed that vacuolar fusion is an important feature of vacuole-mediated PCD in plants. In this experiment, the process of vacuole fusion was accompanied by changes in the structure of actin filaments (AFs), specifically, their depolymerization and polymerization. The process of vacuolar fusion was accelerated or delayed by the promotion or inhibition of the depolymerization of AFs, respectively. Here, the inhibition of OsVPE3 blocked the depolymerization of AFs and delayed the fusion of vacuoles, indicating that OsVPE3 can regulate the fusion of vacuoles in rice aleurone layers via mediating AFs. Furthermore, the depolymerization of AFs contributed to the up-regulation of OsVPE3 gene expression and VPE activity, resulting in accelerated PCD in rice aleurone layers. However, the inhibitor of VPE reversed the effects of AF depolymerization on the activity of VPE, then postponing the process of PCD, implying that AF can involve in GA-induced PCD of rice aleurone layers by mediating OsVPE3. CONCLUSIONS: Together, activation of OsVPE3 and depolymerization of AFs shortened the process of vacuolation and PCD in rice aleurone layers, and OsVPE3 interacted with AFs during regulation.

7.
Front Plant Sci ; 9: 84, 2018.
Article in English | MEDLINE | ID: mdl-29449858

ABSTRACT

Hydrogen peroxide (H2O2) is a reactive oxygen species (ROS) that plays a dual role in plant cells. Here, we discovered that drought (20% polyethylene glycol-6000, PEG)-triggered decreases of HO-1 transcript expression and HO activity. However, exogenous H2O2 contributed toward the increase in HO-1 gene expression and activity of the enzyme under drought stress. Meanwhile, the HO-1 inducer hematin could mimic the effects of the H2O2 scavengers ascorbic acid (AsA) and dimethylthiourea (DMTU) and the H2O2 synthesis inhibitor diphenyleneiodonium (DPI) for scavenging or diminishing drought-induced endogenous H2O2. Conversely, the zinc protoporphyrin IX (ZnPPIX), an HO-1-specific inhibitor, reversed the effects of hematin. We further analyzed the endogenous H2O2 levels and HO-1 transcript expression levels of aleurone layers treated with AsA, DMTU, and DPI in the presence of exogenous H2O2 under drought stress, respectively. The results showed that in aleurone layers subjected to drought stress, when the endogenous H2O2 level was inhibited, the effect of exogenous H2O2 on the induction of HO-1 was enhanced. Furthermore, exogenous H2O2-activated HO-1 effectively enhanced amylase activity. Application of 8-bromoguanosine 3',5'-cyclic guanosine monophosphate (8-Br-cGMP) (the membrane permeable cGMP analog) promoted the effect of exogenous H2O2-delayed PCD of aleurone layers in response to drought stress. More importantly, HO-1 delayed the programmed cell death (PCD) of aleurone layers by cooperating with nitric oxide (NO), and the delayed effect of NO on PCD was achieved via mediation by cGMP under drought stress. In short, in rice aleurone layers, exogenous H2O2 (as a signaling molecule) triggered HO-1 and delayed PCD via cGMP which possibly induced amylase activity under drought stress. In contrast, as a toxic by-product of cellular metabolism, the drought-generated H2O2 promoted cell death.

8.
Zhongguo Zhong Yao Za Zhi ; 42(9): 1646-1651, 2017 May.
Article in Chinese | MEDLINE | ID: mdl-29082684

ABSTRACT

"Assessing the quality by distinguishing features of traditional Chinese medicinal materials" is a characteristic quality evaluation system of traditional Chinese medicine, and it is also the basis of "Rating according to characters and setting the price by the grade" on the market. Astragali Radix was regarded as a famous traditional Chinese medicine (TCM), and this paper has carried out herbal textual research on the development and formation of the concept, "assessing the quality by distinguishing features of traditional Chinese medicinal materials", of Astragali Radix. The authentic medicine producing areas of Astragalus in China have experienced a great change, Gansu , Sichuan and adjacent areas before the Tang Dynasty; Shanxi during the Tang and Song Dynasty. The concept, "assessing the quality by distinguishing features of traditional Chinese medicinal materials", of Astragali Radix was formed in the Song and Ming Dynasty and still used today, which described as that the shape is "straight as an arrow"; the texture is "soft as cotton"; the section looks like" gold well and jade hurdle"; it was sweet in taste and has beany flavor. The system, "assessing the quality by distinguishing features of traditional Chinese medicinal materials", of Astragali Radix has undergone the adjustments from "true or false" to "good or bad", advance with the times, pick out the advantages from others and absorb the experience of traditional identification actively. Besides, it always returns to laconism from erudition and was summarized highly. Assessing the quality by distinguishing features of traditional Chinese medicinal materials and commodity specifications have the same root, so the former has reference meaning to revise the latter.


Subject(s)
Astragalus Plant/chemistry , Drugs, Chinese Herbal/standards , China , Medicine, Chinese Traditional , Pharmacopoeias as Topic , Plant Roots
9.
Chin Med ; 12: 14, 2017.
Article in English | MEDLINE | ID: mdl-28533813

ABSTRACT

BACKGROUND: The content of medicinal bioactive constituents in huangqi is affected by plant age. In this study, we devised a quick and convenient method for determining the age of huangqi, which was cultivated in Hunyuan County (Shanxi Province). METHODS: 1, 2, 3, 4, 5, 8, 10 growth years huangqi had 38 samples, all samples were collected separately. The growth rings in these samples were observed after making paraffin section and freehand-section. The relationship between growth rings and its growth years was analyzed by SPSS 19.0 software. Histochemical localization of total flavones and saponins in huangqi was determined by color reactions. The concentration of four flavonoids and two saponins in the roots of huangqi of different ages and different organizational structure (normal roots and rotten heart roots) were determined by HPLC-DAD and HPLC-ELSD. The results were analyzed by SPSS 19.0 software. RESULTS: All huangqi samples had clear growth rings, and the statistical result about growth rings (X) and growth years (Y) showed significant correlation (r = 1, P = 0.000). The calibration curves of these six ingredients showed good linearity respectively, with significant correlation. All relative standard deviations (RSDs) of precision, recovery, repeatability, and stability experiments were less than 2%. Roots of 5-year-old plants contained the highest concentrations of total flavonoids and saponins. Saponin concentrations increased toward the center of the roots, whereas the four flavonoids showed an opposite trend in tissue distribution. CONCLUSION: The growth year of huangqi (Hunyuan County, Shanxi Province) could be determined soon and conveniently by naked eyes after staining phloroglucinol-HCl solution on freehand section. The content of saponins and flavonoids in rotten heart root and the surrounding normal tissues were affected by the formation and the extent of rotten heart.

10.
Sci Rep ; 7: 41245, 2017 01 24.
Article in English | MEDLINE | ID: mdl-28117452

ABSTRACT

Vacuole fusion is a necessary process for the establishment of a large central vacuole, which is the central location of various hydrolytic enzymes and other factors involved in death at the beginning of plant programmed cell death (PCD). In our report, the fusion of vacuoles has been presented in two ways: i) small vacuoles coalesce to form larger vacuoles through membrane fusion, and ii) larger vacuoles combine with small vacuoles when small vacuoles embed into larger vacuoles. Regardless of how fusion occurs, a large central vacuole is formed in rice (Oryza sativa) aleurone cells. Along with the development of vacuolation, the rupture of the large central vacuole leads to the loss of the intact plasma membrane and the degradation of the nucleus, resulting in cell death. Stabilizing or disrupting the structure of actin filaments (AFs) inhibits or promotes the fusion of vacuoles, which delays or induces PCD. In addition, the inhibitors of the vacuolar processing enzyme (VPE) and cathepsin B (CathB) block the occurrence of the large central vacuole and delay the progression of PCD in rice aleurone layers. Overall, our findings provide further evidence for the rupture of the large central vacuole triggering the PCD in aleruone layers.


Subject(s)
Apoptosis , Oryza/cytology , Oryza/metabolism , Vacuoles/metabolism , Actin Cytoskeleton/metabolism , Amino Acid Chloromethyl Ketones/pharmacology , Apoptosis/drug effects , Cathepsin B/antagonists & inhibitors , Cathepsin B/metabolism , Cell Membrane/metabolism , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Cell Nucleus Shape/drug effects , Cysteine Endopeptidases/metabolism , Cytochalasin B/pharmacology , Membrane Fusion/drug effects , Oryza/drug effects , Permeability , Phalloidine/pharmacology , Protoplasts/drug effects , Protoplasts/metabolism , Seeds/cytology , Seeds/metabolism , Vacuoles/drug effects
11.
Zhong Yao Cai ; 38(12): 2487-92, 2015 Dec.
Article in Chinese | MEDLINE | ID: mdl-27352529

ABSTRACT

OBJECTIVE: To investigate the main cultivation areas of Astragalus membranaceus var. mongholicus, and to clarify its present cultivation status and commercial specification grades. METHODS: Astragalus membranaceus var. mongholicus cultivated in Hunyuan and Ying County of Shanxi, Longxi, Weiyuan and Min County of Gansu and Wuchuan, Guyang and Chifeng of Inner Mongolia were investigated, including their ecological environment, cultivation history and present situation, harvesting and processing as well as commercial specification grades. RESULTS: The cultivation methods of Astragalus membranaceus var. mongholicus changed greatly in the main cultivation areas. In Gansu and Inner Mongolia, the current major cultivation method was 2 - 3 years of seedling transplantation method, while the 3 - 5 years of seed-directly-sowed method in Inner Mongolia had been almost abandoned, and the 6 - 8 years of mountain direct seeding method was still in application in Hunyuan county of Shanxi province. On the other hand, the harvest method of Astragalus membranaceus var. mongholicus had been gradually changed from manual harvesting in ancient times to the current mechanical harvesting although the latter method did more damage to environment of cultivation areas and the resource of Astragalus membranaceus var. mongholicus in regions Hunyuan county of Shanxi. Through investigating the processing methods of Astragalus membranaceus var. mongholicus in different cultivation areas, it was found that processing method varied from area to area, and no unified specifications had been formulated on processing methods in market. In addition, the current processing method was too complicated in processing the slices of prepared Astragali Radix and most were self processing by farmers themselves, creating market disorders. Moreover, the Astragali Radix products were basically without grading classification but sold as bulk cargo. CONCLUSION: It is urgent to unify the specifications and grades of Astragali Radix product, and standardize its processing methods.


Subject(s)
Agriculture/methods , Astragalus propinquus/growth & development , Plants, Medicinal/growth & development , China , Drugs, Chinese Herbal/chemistry
12.
Zhongguo Zhong Yao Za Zhi ; 40(22): 4364-9, 2015 Nov.
Article in Chinese | MEDLINE | ID: mdl-27097408

ABSTRACT

Puerariae Lobatae Radix, also known as Gegen, is a root derived from Pueraria lobata. Based on field investigation and the developmental anatomy of root tuber, we have elucidated the relationship between the growth of root tuber and the anomalous structure. The results of analysis showed that the root system of P. lobata was developed from seed and adventitious root and there existed root tuber, adventitious root and conductive root according to morphology and function. The root tuber was developed from adventitious root, its secondary structure conformed to the secondary structure of dicotyledon's root. With the development of root, the secondary phloem of root tuber appeared abnormal vascular tissue, which was distributed like ring in the outside of secondary vascular tissue. The root tuber might have 4-6 concentric circular permutation abnormal vascular tissuelobate, and was formed by the internal development of abnormal vascular tissue. The xylem and phloem of abnormal vascular tissue were the main body of the root tuber. The results reveal the abnormal anatomical structure development of P. lobata, also provides the theoretical basis for reasonable harvest medicinal parts and promoting sustainable utilization of resources of P. lobata.


Subject(s)
Plant Tubers/anatomy & histology , Pueraria/growth & development , Plant Roots/anatomy & histology , Plant Roots/growth & development , Plant Tubers/growth & development , Pueraria/anatomy & histology
13.
Front Plant Sci ; 6: 1267, 2015.
Article in English | MEDLINE | ID: mdl-26834769

ABSTRACT

Cereal aleurone layers undergo a gibberellin (GA)-regulated process of programmed cell death (PCD) following germination. Heme oxygenase-1 (HO-1) is known as a rate-liming enzyme in the degradation of heme to biliverdin IXα, carbon monoxide (CO), and free iron ions (Fe(2+)). It is a critical component in plant development and adaptation to environment stresses. Our previous studies confirmed that HO-1 inducer hematin (Ht) promotes the germination of rice seeds in drought (20% polyethylene glycol-6000, PEG) conditions, but the corresponding effects of HO-1 on the alleviation of germination-triggered PCD in GA-treated rice aleurone layers remain unknown. The present study has determined that GA co-treated with PEG results in lower HO-1 transcript levels and HO activity, which in turn results in the development of vacuoles in aleurone cells, followed by PCD. The pharmacology approach illustrated that up- or down-regulated HO-1 gene expression and HO activity delayed or accelerated GA-induced PCD. Furthermore, the application of the HO-1 inducer Ht and nitric oxide (NO) donor sodium nitroprusside (SNP) not only activated HO-1 gene expression, HO activity, and endogenous NO content, but also blocked GA-induced rapid vacuolation and accelerated aleurone layers PCD under drought stress. However, both HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX) and NO scavenger 2-(4-carboxyphenyl0-4, 4,5,5-tetramethylimidazoline-l-oxyl-3-oxide potassium salt (cPTIO) reserved the effects of Ht and SNP on rice aleurone layer PCD under drought stress by down-regulating endogenous HO-1 and NO, respectively. The inducible effects of Ht and SNP on HO-1 gene expression, HO activity, and NO content were blocked by cPTIO. Together, these results clearly suggest that HO-1 is involved in the alleviation of GA-induced PCD of drought-triggered rice aleurone layers by associating with NO.

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