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1.
Plant Cell Environ ; 46(12): 3680-3703, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37575022

ABSTRACT

Plants have evolved a set of finely regulated mechanisms to respond to various biotic stresses. Transient changes in intracellular calcium (Ca2+ ) concentration have been well documented to act as cellular signals in coupling environmental stimuli to appropriate physiological responses with astonishing accuracy and specificity in plants. Calmodulins (CaMs) and calmodulin-like proteins (CMLs) are extensively characterized as important classes of Ca2+ sensors. The spatial-temporal coordination between Ca2+ transients, CaMs/CMLs and their target proteins is critical for plant responses to environmental stresses. Ca2+ -loaded CaMs/CMLs interact with and regulate a broad spectrum of target proteins, such as ion transporters (including channels, pumps, and antiporters), transcription factors, protein kinases, protein phosphatases, metabolic enzymes and proteins with unknown biological functions. This review focuses on mechanisms underlying how CaMs/CMLs are involved in the regulation of plant responses to diverse biotic stresses including pathogen infections and herbivore attacks. Recent discoveries of crucial functions of CaMs/CMLs and their target proteins in biotic stress resistance revealed through physiological, molecular, biochemical, and genetic analyses have been described, and intriguing insights into the CaM/CML-mediated regulatory network are proposed. Perspectives for future directions in understanding CaM/CML-mediated signalling pathways in plant responses to biotic stresses are discussed. The application of accumulated knowledge of CaM/CML-mediated signalling in biotic stress responses into crop cultivation would improve crop resistance to various biotic stresses and safeguard our food production in the future.


Subject(s)
Calmodulin , Plants , Calmodulin/metabolism , Plants/metabolism , Stress, Physiological , Calcium/metabolism
2.
Semin Ophthalmol ; 38(7): 670-678, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37058000

ABSTRACT

OBJECTIVE: To study the efficacy of Conbercept for the treatment of corneal neovascularization (NV) in a rabbit model. METHODS: NV was induced by placing sutures. Eight rabbits were used as a control. The other 136 rabbits were randomly divided into two equal groups, and 68 rabbits in each group were divided into four subgroups and given different treatments. Time-course photographs, histological examination, and enzyme-linked immunoassay ELISA analysis for vascular endothelial growth factor were performed at weeks 1, 2, and 3 after injection placement. RESULTS: At weeks 1, 2, and 3 after injection placement, there was less expression of corneal NV and VEGF in the conbercept-treated groups than in the saline-treated control groups and less corneal NV and VEGF were expressed in the early treatment group than in the late treatment group. At weeks 2 and 3 after injection, there were fewer corneal NV (length and area) in the early intrastromal injection group with conbercept than in the early subconjunctival injection group with conbercept and a smaller diameter of corneal NV than in the late intrastromal injection group treated with conbercept. Histological examination showed a smaller diameter of corneal NV in all eyes in conbercept-treated groups 1 w after injection than before injection. Treatment with subconjunctival injection with conbercept led to a larger diameter at weeks 2 and 3 than at week 1. CONCLUSIONS: Subconjunctival and intrastromal administrations of conbercept effectively inhibit corneal NV in rabbits, and the latter has the better effect. The effect is the best in the group with cornea intrastromal injection of conbercept 1 w after suture. Early administration of conbercept may successfully inhibit corneal NV in an animal model.


Subject(s)
Angiogenesis Inhibitors , Corneal Neovascularization , Animals , Humans , Rabbits , Bevacizumab/therapeutic use , Corneal Neovascularization/drug therapy , Corneal Neovascularization/metabolism , Corneal Neovascularization/pathology , Vascular Endothelial Growth Factor A , Antibodies, Monoclonal, Humanized/pharmacology , Antibodies, Monoclonal, Humanized/therapeutic use , Disease Models, Animal
3.
Stem Cell Res Ther ; 13(1): 228, 2022 06 03.
Article in English | MEDLINE | ID: mdl-35659288

ABSTRACT

BACKGROUND: Corneal transplantation is the only way to treat serious corneal diseases caused by corneal endothelial dysfunction. However, the shortage of donor corneal tissues and human corneal endothelial cells (HCECs) remains a worldwide challenge. We cultivated HCECs by the use of a conditioned medium from orbital adipose-derived stem cells (OASC-CM) in vitro. Then the HCECs were used to treat animal corneal endothelial dysfunction models via cell transplantation. The purpose of this study was to conduct a long-term observation and evaluation after cell transplantation. METHODS: Orbital adipose-derived stem cells (OASCs) were isolated to prepare the conditioned medium (CM). HCECs were cultivated and expanded by the usage of the CM (CM-HCECs). Then, related corneal endothelial cell (CEC) markers were analyzed by immunofluorescence. The cell proliferation ability was also tested. CM-HCECs were then transplanted into monkey corneal endothelial dysfunction models by injection. We carried out a 24-month postoperative preclinical observation and verified the long-term effect by histological examination and transcriptome sequencing. RESULTS: CM-HCECs strongly expressed CEC-related markers and maintained polygonal cell morphology even after 10 passages. At 24 months after cell transplantation, there was a CEC density of more than 2400 cells per square millimeter (range, 2408-2685) in the experimental group. A corneal thickness (CT) of less than 550 µm (range, 490-510) was attained. Gene sequencing showed that the gene expression pattern of CM-HCECs was similar to that of transplanted cells and HCECs. CONCLUSIONS: Transplantation of CM-HCECs into monkey corneal endothelial dysfunction models resulted in a transparent cornea after 24 months. This research provided a promising prospect of cell-based therapy for corneal endothelial diseases.


Subject(s)
Corneal Diseases , Vascular Diseases , Animals , Cells, Cultured , Cornea , Corneal Diseases/therapy , Culture Media, Conditioned/metabolism , Endothelial Cells/metabolism , Endothelium, Corneal/metabolism , Humans , Vascular Diseases/metabolism
4.
Plant Sci ; 319: 111250, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35487659

ABSTRACT

Calcium/calmodulin signals are important for various cellular and physiological activities in plants. Calmodulin binding transcription activators also named Signal Responsive (SR) proteins belong to an important calcium/calmodulin-dependent transcription factor family that plays critical roles in stress responses. However, the role of SRs in abscisic acid (ABA) regulated plant responses to drought stress is largely unknown. Here, we characterized the role of Arabidopsis SR1 in drought stress tolerance and ABA response by analyzing the phenotypes of SR1 knockout and SR1-overexpression plants. sr1 mutants which accumulate salicylic acid (SA) were found more sensitive to drought stress and showed a higher water loss rate as compared with wild-type. By contrast, SR1-overexpression lines exhibited increased drought tolerance and less water loss than wild-type. Furthermore, sr1 mutants showed reduced ABA response in seed germination, root elongation, and stomatal closure, while SR1-overexpression lines displayed more sensitive to ABA than wild-type. In addition, the drought-sensitive and ABA-insensitive phenotypes of sr1 mutants were recovered by diminishing SA accumulation via knockouts of SA synthesizer ICS1 or activator PAD4, or through expression of SA-degrading enzyme NahG. Some drought/ABA-responsive genes exhibited differentially expressed in sr1 mutants and SR1-overexpression plants. These results suggest that SR1 plays a positive role in drought stress tolerance and ABA response, and drought/ABA responses are antagonized by SA accumulation that is negatively regulated by SR1.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Abscisic Acid/metabolism , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Calcium/metabolism , Calmodulin/genetics , Calmodulin/metabolism , Droughts , Gene Expression Regulation, Plant , Salicylic Acid/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Water/metabolism
5.
J Ophthalmol ; 2021: 5597003, 2021.
Article in English | MEDLINE | ID: mdl-34373790

ABSTRACT

PURPOSE: To evaluate efficacy and safety of novel tricyclic corneal stroma injection (TCSI) voriconazole for the treatment of fungal keratitis. METHODS: This retrospective cohort study included data of 57 patients (57 eyes) with fungal keratitis. The TCSI group consisted of 27 patients (27 eyes) who were injected voriconazole once via TCSI procedure within one week after enrollment, in addition to conventional antifungal treatment. The control group consisted of 30 patients (30 eyes) who were treated using conventional antifungal treatment modalities. The outcome measures consist of the 3-week and 3-month best-corrected visual acuity (BCVA) values and size of infiltrate or scar, time to re-epithelialization, corneal perforation rate and/or therapeutic penetrating keratoplasty (TPK) requirement, the preoperative and post-TCSI corneal endothelial cell density (ECD), and the intraocular pressure (IOP) of the treated eye and the respective contralateral eye. RESULTS: There were no significant differences in the baseline demographic and clinical characteristics between the two groups. 3 weeks and 3 months after enrollment, the TCSI group exhibited an increase in visual acuity (P < 0.05), and there was no significant difference in the size of infiltrate or scar between two groups (P > 0.05). Time to re-epithelialization was shorter in the TCSI group than in the control group (P < 0.05). There was no statistically significant difference between corneal ECD on the day before and 7 days after TCSI and the IOP of treated and contralateral healthy eyes on the day before and 1 day, 3 days, 7 days, and 1 month after TCSI (P > 0.05). The difference in the risk of perforation and/or TPK requirement was not statistically significant between two groups (P > 0.05). CONCLUSION: Localized injection of voriconazole using TCSI may be a minimally invasive, safe, and effective adjuvant treatment modality for fungal keratitis.

6.
Cell Transplant ; 30: 9636897211017830, 2021.
Article in English | MEDLINE | ID: mdl-34053246

ABSTRACT

Corneal endothelial dysfunction is a principal cause of visual deficiency. Corneal transplantation is the most effective treatment for corneal endothelial dysfunction. However, a severe shortage of available donor corneas or human corneal endothelial cells (HCECs) remains a global challenge. Previously, we acquired corneal endothelial cell-like cells (CEC-like cells) derived from human skin-derived precursors (SKPs). CEC-like cells were injected into rabbit and monkey corneal endothelial dysfunction models and exerted excellent therapeutic effect. In this study, we prolonged the clinical observation in the monkey experiment for 2 years. Polymerase chain reaction (PCR) and DNA sequencing were carried out to confirm the existence of CEC-like cells. Histological examinations were carried out to show the corneal morphology. Further transcriptome sequencing was also carried out on HCEC, CEC-like cells before transplantation and after transplantation. We found that the monkeys cornea remained transparent and normal thickness. The total endothelial cell density decreased gradually, but tended to be stable and remained in a normal range during 2-year observation. The CEC-like cells persist during observation and could adapt to the microenvironment after transplantation. The gene expression pattern of CEC-like cells was similar to HCEC and changed slightly after transplantation. In conclusion, this study presented a brand-new insight into CEC-like cells and further provided a promising prospect of cell-based therapy for corneal endothelial dysfunction. The renewable cell source, novel derivation method and simple treatment strategy may be clinically applied in regenerative medicine in the future.


Subject(s)
Cornea/metabolism , Endothelial Cells/metabolism , Animals , Cells, Cultured , Cornea/cytology , Corneal Transplantation , Humans , Macaca mulatta
7.
Stem Cells Dev ; 30(6): 301-308, 2021 03.
Article in English | MEDLINE | ID: mdl-33487117

ABSTRACT

Secreted protein acidic and rich in cysteine (SPARC) shows a specific colocalization with limbal epithelial stem cells (LESCs) in vivo; however, the inherent relationship between SPARC and LESCs is still unclear. This study investigated the effects of SPARC on the maintenance of LESC stemness and corneal wound healing. To test the influence of different concentration of exogenous SPARC on the proliferation of LESCs, cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine staining were performed and the results indicated that 1 µg/mL SPARC was the optimum concentration for enhanced LESC proliferation. Compared with a control group, SPARC-treated group showed a higher expression of LESC-positive markers p63α, ABCG-2, and Bmi-1, and a lower level of differentiation marker cytokeratin-3 (CK3), thereby suggesting that SPARC could maintain LESC characteristic phenotype and suppress spontaneous epithelial differentiation in vitro. In vivo, exogenous SPARC accelerated the wound-healing process by both the enhancement of LESC proliferation and promoting the migration of the proliferating cells. However, the intact epithelium impaired this function of SPARC by contact inhibition.


Subject(s)
Cell Movement/drug effects , Cell Proliferation/drug effects , Epithelium, Corneal/drug effects , Osteonectin/pharmacology , Stem Cells/drug effects , Wound Healing/drug effects , ATP Binding Cassette Transporter, Subfamily G, Member 1/metabolism , Animals , Blotting, Western , Cells, Cultured , Epithelial Cells/cytology , Epithelium, Corneal/physiopathology , Humans , Limbus Corneae/cytology , Mice , Mice, Inbred C57BL , NIH 3T3 Cells , Rabbits , Stem Cells/cytology , Stem Cells/metabolism
8.
PLoS One ; 15(10): e0239939, 2020.
Article in English | MEDLINE | ID: mdl-33057425

ABSTRACT

To provide the general information on corneal transplantation (CT) in China, China Cornea Society designed a questionnaire on CT from 2014 to 2018 and entrusted it to 31 committee members for implementation of the survey nationwide. This article presents the results of the survey and compares the indicators used in the survey and those in the annual statistical report released by the Eye Bank Association of America (EBAA). The number of corneal transplantations completed by the 64 hospitals from 2014 to 2018 was respectively 5377, 6394, 7595, 8270 and 8980, totally 36,616 (22,959 male and 13,657 female). The five largest hospitals by the number of corneal transplantations completed 15,994 surgeries in total, accounting for 43.68% of all the surgeries performed in the 64 hospitals. The most common indication for corneal transplantations was corneal leukoma (7683, 20.98%), followed by bacterial keratitis (4209, 11.49%), corneal dystrophies (4189, 11.44%), keratoconus (3578, 9.77%) and corneal perforation (2839, 7.75%). The main surgical techniques were penetrating keratoplasty (PK) (19,896, 54.34%), anterior lamellar keratoplasty (ALK) (13,869, 37.88%). The proportion of PK decreased from 57.97% in 2014 to 52.88% in 2018 while the proportion of ALK increased from 36.04% in 2014 to 37.92% in 2018. The geographical distribution of keratoplasties performed in China is unbalanced. PK and ALK were the main techniques of CT and corneal leukoma, bacterial keratitis and corneal dystrophies were the main indications for CT in China.


Subject(s)
Cornea , Corneal Diseases , Corneal Transplantation , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , China , Cornea/pathology , Cornea/surgery , Corneal Diseases/epidemiology , Corneal Diseases/surgery , Corneal Transplantation/methods , Corneal Transplantation/statistics & numerical data , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies , Surveys and Questionnaires , Young Adult
9.
BMC Ophthalmol ; 20(1): 285, 2020 Jul 13.
Article in English | MEDLINE | ID: mdl-32660455

ABSTRACT

BACKGROUND: We report a case of spontaneous resolution of a traumatic cataract in a patient with an open-globe ocular injury. This case highlights the importance of conservative management in these types of cases, as excellent visual outcome is possible without invasive surgical intervention. CASE PRESENTATION: A 13-year-old boy presented with a corneal laceration in the left eye caused by a neuter pen. He underwent emergency repair of the corneal laceration under general anesthesia, and at 3 days post-op, a dense posterior cortical cataract was observed. Based on the patient's age and normal visual development, in addition to preserving accommodative potential, the patient received conservative management and follow-up. Interestingly, the cataract spontaneously resolved over the following 9 months and the corrected distance visual acuity in the injured eye was restored from finger counting at 50 cm, to 20/25 + 3. CONCLUSIONS: To optimize treatment in pediatric traumatic cataract, several critical factors such as age, visual development and the preservation of accommodative potential, need to be comprehensively considered. Conservative management with lens preservation is important to consider in young, traumatic cataract patients where invasive surgical intervention may not be required.


Subject(s)
Cataract Extraction , Cataract , Eye Injuries, Penetrating , Lens, Crystalline , Adolescent , Cataract/etiology , Child , Eye Injuries, Penetrating/surgery , Humans , Lens Implantation, Intraocular , Lens, Crystalline/injuries , Male , Retrospective Studies
10.
Ultrasonics ; 103: 106100, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32044567

ABSTRACT

The fabrication of high-aspect-ratio metal micro device on metal substrate is largely limited by its poor interfacial adhesion strength between metal substrate and thick SU-8 photoresist mould. In this paper, ultrasonic treatment is introduced to improve the interfacial adhesion strength between metal substrate and a high-aspect-ratio inertial switch SU-8 mould. Firstly, a device for ultrasonic treatment was developed, ultrasonic vibration is applied to SU-8 film after post exposure baking in order to improve the interfacial adhesion strength. Compared with the traditional one, SU-8 photoresist mould treated by ultrasonic vibration can effectively improve the interfacial adhesion strength. After 90 min cavitation erosion test, SU-8 film treated by ultrasonic vibration remains 34.4% relative to nothing left of the SU-8 film without ultrasonic treatment. Besides, the mechanisms of ultrasonic treatment on improving interfacial adhesion strength are investigated. Finally, an inertial switch is successfully fabricated on metallic substrate with the ultrasonic treated SU-8 photoresist mould.

11.
Ultrasonics ; 100: 105990, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31479968

ABSTRACT

Through-mask electrochemical micromachining (TMEMM) is the primary method to fabricate micro pits with controlled size, location, and density. In order to improve the machining localization and deep etching capability in TMEMM process, a novel method which combined megasonic vibration to TMEMM process is presented in this paper. Firstly, the coupling relationship between sound field, gas-liquid two-phase flow field and electrolytic process was theoretically analyzed. Theoretical analysis results indicate that acoustic wave agitation can promote the electrolytic process by increasing the conductivity of the electrolyte. Based on this theory, a numerical simulation method was used to predict anodic profiles under different megasonic intensity. The simulation results show that the addition of megasonic agitation can obviously improve the machining localization and deep etching capability in TMEMM process. Etching depth of the micro pit increased from 48.22 µm to 77.98 µm with megasonic agitation compared to the without megasonic one. Depth-diameter ratio of the micro pit increased from 0.30 to 0.45. Meanwhile, the etching factor (EF) increased from 1.55 to 2.10. Then, a megasonic electrolyser at 1 MHz was set up, micro pits were etched under different megasionc intensity. The experiment results show that megasonic assisted through-mask electrochemical micromachining (MA-TMEMM) had best process performance when it worked with the increase of megasionc intensity. When the megasonic intensity was 8 W/cm2, micro pits with average diameter of 167.77 µm and 79.62 µm in depth were successfully fabricated. The average depth-diameter ratio of the micro pits was as high as 0.47, and the EF was as high as 2.35. The working mechanism of megasonic in MA-TMEMM process was analyzed too.

12.
Curr Eye Res ; 45(2): 134-143, 2020 02.
Article in English | MEDLINE | ID: mdl-31514545

ABSTRACT

Purpose: To produce an acellular small intestine submucosa (SIS) that would be a suitable scaffold for corneal epithelium tissue engineering.Methods: The SIS was decellularized by immersion in 0.1% (wt/vol) sodium dodecyl sulfate (SDS). The efficacy of acellularization was confirmed by histological observation and DNA quantification. The mechanical properties were evaluated by uniaxial tensile testing. ELISA was performed to assess the growth factor contents. The cytotoxicity of SIS scaffolds and extracts to rabbit corneal epithelial cells was determined by CCK-8 assay. We also investigated the inflammatory reaction of SIS implanted subcutaneously in a rat. The biocompatibility was studied by rabbit interlamellar corneal transplantation and reseeding assay with cornea-derived cells. Immunofluorescent staining was used to detect the expression of CK3, ZO-1 and K13.Results: Histological analyses showed that complete cell removal was achieved, and the DNA quantity, which reflects the presence of cellular materials, was significantly diminished in acellular SIS. Collagen fibers were properly preserved and appeared in an orderly fashion. The tissue structure, the mechanical properties and the growth factor contents within the acellular SIS were well retained. The CCK8 assay demonstrated that the acellular SIS scaffolds and extracts had no cytotoxicity to rabbit corneal epithelial cells. There was no sign that an immune reaction occurred with acellular SIS implanted subcutaneously in a rat. In fact, in vivo implantation to rabbit interlamellar stromal pockets showed good biocompatibility. We also observed that clusters of rabbit corneal epithelial cells were growing well on the surface of the SIS in vitro and the distinctive CK3, ZO-1 for corneal epithelial cells was detected.Conclusions: The decellularized SIS retained the major structural components. The matrix is biocompatible with cornea-derived cells and might be a suitable scaffold for corneal epithelium tissue engineering.


Subject(s)
Cell-Free System/transplantation , Corneal Transplantation , Epithelium, Corneal/surgery , Intestinal Mucosa/cytology , Intestine, Small/cytology , Tissue Engineering/methods , Tissue Scaffolds , Animals , Bioprosthesis , Cell-Free System/physiology , Cell-Free System/ultrastructure , Enzyme-Linked Immunosorbent Assay , Epithelium, Corneal/metabolism , Epithelium, Corneal/ultrastructure , Fluorescent Antibody Technique, Indirect , Keratin-13/metabolism , Keratin-3/metabolism , Male , Materials Testing , Microscopy, Electron , Rabbits , Rats , Rats, Sprague-Dawley , Subcutaneous Tissue/transplantation , Sus scrofa , Zonula Occludens-1 Protein/metabolism
13.
Stem Cells ; 38(1): 134-145, 2020 01.
Article in English | MEDLINE | ID: mdl-31644832

ABSTRACT

The purpose of this study was to investigate the effects of secreted protein acidic and rich in cysteine (SPARC) on the maintenance of limbal epithelial stem cell (LESC) stemness and restoration of ocular surface. To determine the suitable concentration of SPARC for LESC culture, the marker expression, mitogenic effect, and holoclone-forming capacity of LESCs treated with different concentrations of SPARC were analyzed. To investigate the mechanism of SPARC's action on the preservation of LESCs stemness, the phosphorylation of related signaling pathways was evaluated by Western blotting. A corneal wound model was established to verify the function of SPARC in ocular surface repair. Consecutive subculturing, colony-forming efficiency, immunofluorescence, and 5-ethynyl-2-deoxyuridine incorporation assays indicated that 1 µg/mL SPARC was a suitable concentration to stimulate LESC proliferation and preserve their proliferative potential. Compared with a control group, 1 µg/mL SPARC effectively increased the expression of ABCG-2, Bmi-1, and Ki67, while decreasing that of CK3/12. The mitogenic effect of SPARC on LESCs was found to be mediated by the phosphorylation of c-Jun N-terminal kinase (JNK) and p38-MAPK signaling pathways, whereas the inhibitors of JNK and p38 MAPK reduced the marker expression and mitogenic capacity of LESCs. In a corneal injury model, SPARC facilitated corneal epithelial wound healing and promoted the proliferation of p63α-positive cells both in the limbus and in the epithelial healing front. SPARC promotes proliferation while suppressing spontaneous differentiation of LESCs through JNK and p38-MAPK signaling pathways, suggesting that SPARC is a promising factor for the improvement of LESCs culture in vitro and in vivo.


Subject(s)
Epithelial Cells/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Limbus Corneae/metabolism , Osteonectin/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , 3T3 Cells , Animals , Cell Differentiation/physiology , Cell Proliferation/physiology , Epithelial Cells/cytology , Humans , MAP Kinase Signaling System , Mice , Rabbits
14.
Mol Cell Proteomics ; 18(11): 2225-2243, 2019 11.
Article in English | MEDLINE | ID: mdl-31467032

ABSTRACT

Soybean (Glycine max (L.) Merrill) is an important component of the human diet and animal feed, but soybean production is limited by abiotic stresses especially salinity. We recently found that rhizobia inoculation enhances soybean tolerance to salt stress, but the underlying mechanisms are unaddressed. Here, we used quantitative phosphoproteomic and metabonomic approaches to identify changes in phosphoproteins and metabolites in soybean roots treated with rhizobia inoculation and salt. Results revealed differential regulation of 800 phosphopeptides, at least 32 of these phosphoproteins or their homologous were reported be involved in flavonoid synthesis or trafficking, and 27 out of 32 are transcription factors. We surveyed the functional impacts of all these 27 transcription factors by expressing their phospho-mimetic/ablative mutants in the roots of composite soybean plants and found that phosphorylation of GmMYB183 could affect the salt tolerance of the transgenic roots. Using data mining, ChIP and EMSA, we found that GmMYB183 binds to the promoter of the soybean GmCYP81E11 gene encoding for a Cytochrome P450 monooxygenase which contributes to the accumulation of ononin, a monohydroxy B-ring flavonoid that negatively regulates soybean tolerance to salinity. Phosphorylation of GmMYB183 was inhibited by rhizobia inoculation; overexpression of GmMYB183 enhanced the expression of GmCYP81E11 and rendered salt sensitivity to the transgenic roots; plants deficient in GmMYB183 function are more tolerant to salt stress as compared with wild-type soybean plants, these results correlate with the transcriptional induction of GmCYP81E11 by GmMYB183 and the subsequent accumulation of ononin. Our findings provide molecular insights into how rhizobia enhance salt tolerance of soybean plants.


Subject(s)
Flavonoids/biosynthesis , Glycine max/metabolism , Phosphoproteins/metabolism , Plant Proteins/metabolism , Rhizobium/metabolism , Salt Tolerance , Transcription Factors/metabolism , Gene Expression Regulation, Plant , Metabolome , Phosphoproteins/genetics , Phosphorylation , Plant Proteins/genetics , Proteome/analysis , Glycine max/genetics , Glycine max/growth & development , Transcription Factors/genetics
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(1): 172-176, 2019 Feb 25.
Article in Chinese | MEDLINE | ID: mdl-30887793

ABSTRACT

Dental pulp stem cells(DPSCs) are adult stem cells with strong proliferative ability, self-renewal ability and multidirectional differentiation potential. DPSCs have abundant source are easy to obtain, and do not have ethical problems. As seed cells, they played an important role and showed great potential in tissue engineering and regenerative medicine, making them potential ideal seed cells for repairation and regeneration of tissue and organ. Clinical application of DPSCs in bone regeneration has already been achieved, and studies on differentiation of DPSCs into other tissues are still at different levels of basic stage. In this paper, the research and application of directional differentiation potential such as tooth formation, osteogenesis, and nerve formation are reviewed in order to provide clues and ideas for further study on DPSCs in the field of tissue engineering and regenerative medicine.

16.
Ultrason Sonochem ; 48: 424-431, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30080569

ABSTRACT

This paper explores the mass transfer mechanism of microvias electroforming under ultrasonic agitation by numerical simulations and electrochemical experiments. Firstly, the velocity distribution of electroforming solution inside the microvias under ultrasound treatment is simulated by COMSOL Multiphysics software. The ultrasonic frequency is that of 120 kHz. The ultrasonic powers are 100 W, 200 W, 300 W and 400 W, respectively. The simulation results indicate that the mean liquid velocity inside the microvias increases with the increasing of acoustic power. In addition, under a certain ultrasonic power, the mean liquid velocity will decrease with increasing the distance between microvias and transducer, the aspect ratio of microvias and the distance between cathode and central position. Secondly, electrochemical experiments are presented to investigate the effect of ultrasonic agitation on the electrode kinetics of microvias electroforming. It is found that ultrasonic treatment decreases the thickness of diffusion layer, increases the limiting diffusion current densities and further enhances the mass transfer of microvias electroforming. Compared with the silent condition, the diffusion layer thicknesses with the acoustic power of 100 W, 200 W, 300 W, 400 W are decreased by 50.0%, 64.1%, 69.3% and 74.5%, respectively. Finally, according to the results above, the 200 × 200 metal micro-column array structures are fabricated by ultrasonic electroforming under the condition of 120 kHz and 200 W. The metal micro-column is 250 µm high and has a diameter of 80 µm. The results show that ultrasonic electroforming can enhance the mass transfer of microvias electroforming, and further solve the problem of porous structure in electroforming layer. This work contributes to expanding the application of ultrasonic agitation in the microvias electroforming.

17.
Ultrason Sonochem ; 49: 233-240, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30139636

ABSTRACT

In order to reduce the large residual stress in micro elelctroforming layer, megasonic assisted electroforming is proposed here. Micro electroforming experiments were performed with and without megasonic agitation, respectively. Four different megasonic power densities were applied to investigate the influence of megasonic agitation on reducing the residual stress. The residual stress was measured by X-ray diffraction (XRD) method. Experiment results show that the residual stresses fabricated with megasonic agitation are less than that fabricated without megasonic. When the megasonic power density is 2 W/cm2, the residual stress can be the minimum value of -125.7 MPa, reduced by 60% in comparison with the value of -315.1 MPa electroformed without megasonic agitation. For exploring the mechanism of megasonic agitation on reducing the residual stress, the dislocation density and crystal orientation were calculated by the single-line Voigt profile analysis and Relative Texture Coefficient (RTC) method, respectively. The diameters and distributions of pits on the surface of electroforming layer were observed by the STM-6 tool microscope and counted by the Image-Pro Plus software. It reveals that one hand of the mechanism is the acoustic streaming produced by megasonic can strengthen the motion of dislocation in crystal lattice and makes the crystal lattices grow towards the equilibrium shape, which is benefit to crystallization with low residual stress. When the megasonic power density is 2 W/cm2, the dislocation density increases to be the maximum value of 8.09 × 1015 m-2 and the difference between RTC(1 1 1) and RTC(2 0 0) decreases to be zero, which is consistent with the residual stress results. The other hand is that the stable cavitation produced by megasonic can provide residual stress release points during the electroforming process.

18.
Med Sci Monit ; 24: 5208-5215, 2018 Jul 27.
Article in English | MEDLINE | ID: mdl-30051889

ABSTRACT

BACKGROUND The aim of this study was to evaluate the feasibility of using a femto-laser in assisting xenograft cornea matrix lens transplantation in correcting ametropia, along with evaluating the effectiveness and predictability of this procedure. MATERIAL AND METHODS A corneal matrix pouch was prepared on the right eyes on 8 healthy New Zealand rabbits by a femto-laser that was also employed to perform small incision lenticule extraction (SMILE) on 8 bovine cornea matrix lenses (+6D). A lens was treated acellular and implanted into a right rabbit cornea matrix pouch. Surface inflammation was observed at 1, 2, 4, 8, 12, and 24 weeks after surgery. Anterior ocular segment optical coherence tomography (OCT), corneal topography, retinoscopy, and cornea endothelial cell enumeration were performed. RESULTS All the surgeries were successfully performed without any complications. The hyperopia condition of the rabbit eyes transformed into myopia status at an early stage and gradually developed hyperopia. Diopter at 24 weeks after surgery was 1/3 of that before surgery. Central corneal thickness stabilized at 4 weeks after surgery. Anterior segment OCT showed a clear lens edge at early post-operative stage, and blurred edge at 24 weeks later, indicating gradual fusion with the rabbit corneal matrix. CONCLUSIONS Femto-laser assisted xenograft corneal matrix lens transplantation is safe and effective in correcting ametropia, with satisfactory predictability, thus providing novel choice for correcting ametropia.


Subject(s)
Corneal Transplantation/methods , Refractive Errors/therapy , Transplantation, Heterologous/methods , Animals , Cattle , Cornea , Corneal Topography , Female , Heterografts/physiology , Hyperopia/surgery , Laser Therapy/methods , Lasers, Excimer/therapeutic use , Male , Myopia/surgery , Rabbits , Refractive Surgical Procedures/methods , Tomography, Optical Coherence
19.
Int J Mol Sci ; 19(6)2018 06 14.
Article in English | MEDLINE | ID: mdl-29899210

ABSTRACT

During plant-pathogen interactions, plants have to relocate their resources including energy to defend invading organisms; as a result, plant growth and development are usually reduced. Arabidopsis signal responsive1 (AtSR1) has been documented as a negative regulator of plant immune responses and could serve as a positive regulator of plant growth and development. However, the mechanism by which AtSR1 balances plant growth and immunity is poorly understood. Here, we performed a global gene expression profiling using Affymetrix microarrays to study how AtSR1 regulates defense- and growth-related genes in plants with and without bacterial pathogen infection. Results revealed that AtSR1 negatively regulates most of the immune-related genes involved in molecular pattern-triggered immunity (PTI), effector-triggered immunity (ETI), and in salicylic acid (SA)- and jasmonate (JA)-mediated signaling pathways. AtSR1 may rigidly regulate several steps of the SA-mediated pathway, from the activation of SA synthesis to the perception of SA signal. Furthermore, AtSR1 may also regulate plant growth through its involvement in regulating auxin- and BRs-related pathways. Although microarray data revealed that expression levels of defense-related genes induced by pathogens are higher in wild-type (WT) plants than that in atsr1 mutant plants, WT plants are more susceptible to the infection of virulent pathogen as compared to atsr1 mutant plants. These observations indicate that the AtSR1 functions in suppressing the expression of genes induced by pathogen attack and contributes to the rapid establishment of resistance in WT background. Results of electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-PCR assays suggest that AtSR1 acts as transcription factor in balancing plant growth and immunity, through interaction with the "CGCG" containing CG-box in the promotors of its target genes.


Subject(s)
Arabidopsis Proteins/genetics , Arabidopsis/genetics , Plant Development , Plant Immunity , Arabidopsis/growth & development , Arabidopsis/immunology , Arabidopsis/microbiology , Arabidopsis Proteins/metabolism , Calcium/metabolism , Cyclopentanes/metabolism , Gene Expression Regulation, Plant , Oxylipins/metabolism , Salicylic Acid/metabolism , Transcriptional Activation
20.
Mol Cell Proteomics ; 17(6): 1209-1224, 2018 06.
Article in English | MEDLINE | ID: mdl-29496908

ABSTRACT

Salinity causes osmotic stress to crops and limits their productivity. To understand the mechanism underlying soybean salt tolerance, proteomics approach was used to identify phosphoproteins altered by NaCl treatment. Results revealed that 412 of the 4698 quantitatively analyzed phosphopeptides were significantly up-regulated on salt treatment, including a phosphopeptide covering the serine 59 in the transcription factor GmMYB173. Our data showed that GmMYB173 is one of the three MYB proteins differentially phosphorylated on salt treatment, and a substrate of the casein kinase-II. MYB recognition sites exist in the promoter of flavonoid synthase gene GmCHS5 and one was found to mediate its recognition by GmMYB173, an event facilitated by phosphorylation. Because GmCHS5 catalyzes the synthesis of chalcone, flavonoids derived from chalcone were monitored using metabolomics approach. Results revealed that 24 flavonoids of 6745 metabolites were significantly up-regulated after salt treatment. We further compared the salt tolerance and flavonoid accumulation in soybean transgenic roots expressing the 35S promoter driven cds and RNAi constructs of GmMYB173 and GmCHS5, as well as phospho-mimic (GmMYB173S59D ) and phospho-ablative (GmMYB173S59A ) mutants of GmMYB173 Overexpression of GmMYB173S59D and GmCHS5 resulted in the highest increase in salt tolerance and accumulation of cyaniding-3-arabinoside chloride, a dihydroxy B-ring flavonoid. The dihydroxy B-ring flavonoids are more effective as anti-oxidative agents when compared with monohydroxy B-ring flavonoids, such as formononetin. Hence the salt-triggered phosphorylation of GmMYB173, subsequent increase in its affinity to GmCHS5 promoter and the elevated transcription of GmCHS5 likely contribute to soybean salt tolerance by enhancing the accumulation of dihydroxy B-ring flavonoids.


Subject(s)
Flavonoids/metabolism , Glycine max/metabolism , Salt Stress/physiology , Soybean Proteins/metabolism , Transcription Factors/metabolism , Metabolomics , Phosphoproteins/metabolism , Proteomics
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