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1.
Artigo em Inglês | MEDLINE | ID: mdl-38018817

RESUMO

Manganese (Mn)-based layer-structured transition metal oxides are considered as excellent cathode materials for potassium ion batteries (KIBs) owing to their low theoretical cost and high voltage plateau. The energy density and cycling lifetime, however, cannot simultaneously satisfy the basic requirements of the market for energy storage systems. One of the primary causes results from the complex structural transformation and transition metal migration during the ion intercalation and deintercalation process. The orbital and electronic structure of the octahedral center metal element plays an important role for maintaining the octahedral structural integrity and improving the K+ diffusivity by the introduced heterogeneous [Me-O] chemical bonding. A multitransition metal oxide, P3-type K0.5Mn0.85Co0.05Fe0.05Al0.05O2 (KMCFAO), was synthesized and employed as a cathode material for KIBs. Beneficial from the larger layer spacing for K+ to better accommodate and effectively preventing the irreversible structural transformation in the insertion/extraction process, it can reach a superior capacity retention up to 96.8% after 300 cycles at a current density of 500 mA g-1. The full cell of KMCFAO//hard carbon exhibits an encouraging promising energy density of 113.8 W h kg-1 at 100 mA g-1 and a capacity retention of 72.6% for 500 cycles.

2.
Neural Regen Res ; 18(3): 603-608, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36018184

RESUMO

ß2-Microglobulin (ß2M), a component of the major histocompatibility complex class I molecule, is associated with aging-related cognitive impairment and Alzheimer's disease. Although upregulation of ß2M is considered to be highly related to ischemic stroke, the specific role and underlying mechanistic action of ß2M are poorly understood. In this study, we established a rat model of focal cerebral ischemia by occlusion of the middle cerebral artery. We found that ß2M levels in the cerebral spinal fluid, serum, and brain tissue were significantly increased in the acute period but gradually decreased during the recovery period. RNA interference was used to inhibit ß2M expression in the acute period of cerebral stroke. Tissue staining with 2,3,5-triphenyltetrazolium chloride and evaluation of cognitive function using the Morris water maze test demonstrated that decreased ß2M expression in the ischemic penumbra reduced infarct volume and alleviated cognitive deficits, respectively. Notably, glial cell, caspase-1 (p20), and Nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome activation as well as production of the inflammatory cytokines interleukin-1ß, interleukin-6, and tumor necrosis factor-α were also effectively inhibited by ß2M silencing. These findings suggest that ß2M participates in brain injury and cognitive impairment in a rat model of ischemic stroke through activation of neuroinflammation associated with the NLRP3 inflammasome.

4.
Zhongguo Zhong Yao Za Zhi ; 47(9): 2474-2479, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35531695

RESUMO

A new phloroglucinol was isolated from 50% ethanol extract of Dryopteris fragrans by silica gel column chromatography, Sephadex LH-20 gel column chromatography, thin-layer chromatography(TLC), and preparative liquid column chromatography. On the basis of MS, ~1H-NMR, ~(13)C-NMR, and reference materials, compound 1 was identified as 2,5-cyclohexadien-1-one, 2-{[2,6-dihydroxy-4-methoxy-3-methyl-5-(1-isobutyl)phenyl]methyl}-3,5-dihydroxy-4,4-dimethyl-6-(1-oxobutyl)(1), and named disaspidin BB. Compound 1 was evaluated for its antibacterial activity. The experimental results showed that compared with the commonly used topical antibiotics erythromycin or mupirocin, disaspidin BB exhibited significant antibacterial activities against Staphylococcus epidermidis(SEP), S. haemolyticus(SHA), and methicillin-resistant S. aureus(MRSA)(P<0.05). Additionally, disaspidin BB was sensitive to ceftazidime-resistant SEP1-SEP4, SHA5-SHA7, MRSA8, and MRSA9. The MIC values of disaspidin BB against SEP and SHA were 1.67-2.71 µg·mL~(-1) and 10.00-33.33 µg·mL~(-1) respectively. Disaspidin BB has good antibacterial activities and deserves development as a new anti-infective drug for external use.


Assuntos
Dryopteris , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Floroglucinol/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
5.
J Neuroophthalmol ; 40(1): 22-29, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31246675

RESUMO

PURPOSE: Clinical trials of gene therapy for Leber hereditary optic neuropathy (LHON) were conducted in 9 volunteers with the mitochondrial mutation, G11778A in ND4. The purpose of this study was to investigate whether multilocus mitochondrial mutations directly influence the efficacy of gene therapy for LHON. METHODS: Nine volunteers with LHON participated in a clinical trial with intravitreal injection of an adenoviral vector expressing wild-type ND4. Patients were subsequently divided into 2 groups: according to the differences in therapy efficacy and based on improvements in visual acuity. Full mitochondrial DNA sequences of the 2 groups of patients were generated and compared using PubMed, PolyPhen, and PROVEAN. Furthermore, the association between the detected mutations and clinical effects of gene therapy was analyzed. RESULTS: Best-corrected visual acuity (BCVA) significantly improved (≥0.3 log of minimum angle of resolution [logMAR]) in 7 patients 6 months after gene therapy, whereas there was no significant change in BCVA (<0.3 logMAR) of the remaining 2 patients. All 9 patients carried the G1178A mutation in addition to other nonsynonymous mutations. Among these mutations, some were predicted to be neutral and deleterious. Meanwhile, different mitochondrial mutations in the group in which treatment was ineffective, compared with those in responders, were at nucleotide positions 6569 (CO1; Patient 3), 9641 (CO3; Patient 3), and 4491 (ND2; Patient 5). CONCLUSIONS: Detection of the 3 primary mitochondrial mutations causing LHON is sufficient for screening before gene therapy; sequencing of the entire mitochondrial genome is unnecessary before treatment. Patients with LHON can respond to targeted gene therapy irrespective of additional multilocus mitochondrial mutations.


Assuntos
DNA Mitocondrial/genética , Terapia Genética/métodos , Mitocôndrias/genética , Mutação , Atrofia Óptica Hereditária de Leber/terapia , Acuidade Visual/fisiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Óptica Hereditária de Leber/genética , Atrofia Óptica Hereditária de Leber/fisiopatologia , Resultado do Tratamento , Adulto Jovem
6.
Theranostics ; 9(20): 5937-5955, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534530

RESUMO

Prolonged occlusion of multiple microvessels causes microvascular injury. G protein-coupled receptor 124 (GPR124) has been reported to be required for maintaining central nervous system (CNS) angiogenesis and blood-brain barrier integrity. However, the molecular mechanisms by which GPR124 regulates pericytes during ischemia have remained elusive. Methods: A microsphere embolism-induced ischemia model was used to evaluate the expression of GPR124 following microsphere embolism. Immunocytochemistry and stochastic optical reconstruction microscopy imaging were used to assess the expression and distribution of GPR124 in human brain vascular pericytes (HBVPs) and after the treatment with 3-morpholino-sydnonimine (SIN-1) or oxygen-glucose deprivation (OGD). The effect of GPR124 knockdown or overexpression on HBVP migration was analyzed in vitro using wound healing assays and a microfluidic device. GPR124 loss-of-function studies were performed in HBVPs and HEK293 cells using CRISPR-Cas9-mediated gene deletion. Time-lapse imaging was used to assess dynamic changes in the formation of filopodia in an individual cell. Finally, to explore the functional domains required for GPR124 activity, deletion mutants were constructed for each of the N-terminal domains. Results: GPR124 expression was increased in pericytes following microsphere embolism. Morphological analysis showed localization of GPR124 to focal adhesions where GPR124 bound directly to the actin binding protein vinculin and upregulated Cdc42. SIN-1 or OGD treatment redistributed GPR124 to the leading edges of HBVPs where GPR124 signaling was required for pericyte filopodia formation and directional migration. Partial deletion of GPR124 domains decreased SIN-1-induced filopodia formation and cell migration. Conclusion: Taken together, our results provide the first evidence for a role of GPR124 in pericyte migration under ischemic conditions and suggest that GPR124 was essential for Cdc42 activation and filopodia formation.


Assuntos
Isquemia Encefálica/metabolismo , Polaridade Celular/fisiologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Pericitos/citologia , Pericitos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Western Blotting , Linhagem Celular , Polaridade Celular/genética , Adesões Focais/metabolismo , Células HEK293 , Humanos , Imuno-Histoquímica , Imunoprecipitação , Lentivirus/genética , Masculino , Camundongos , Plasmídeos/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/genética , Cicatrização/genética , Cicatrização/fisiologia
7.
Medicine (Baltimore) ; 95(40): e5110, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27749593

RESUMO

Gene therapy may be a promising approach for the treatment of Leber hereditary optic neuropathy. The aim of this study was to evaluate patients with this condition who were recruited into an upcoming gene therapy clinical trial and to assess any changes in the detection parameters to provide support for the clinical trial. Sixteen patients with Leber hereditary optic neuropathy were evaluated using visual function tests 12 months before the initiation of gene therapy. Then, the results of visual acuity (VA), visual field (VF), RNFL (retinal nerve fiber layer) thickness, and Pattern-reversal Visual evoked potential (PR-VEP) were compared and analyzed. A total of 32 eyes of 16 patients were evaluated. Based on the best-corrected visual acuity (BCVA), 24 eyes were relatively stable compared with the baseline evaluation, and 8 eyes had significant changes, including 5 eyes that showed improvement and 3 eyes that showed impairment. In all eyes, the changes in the best-corrected visual acuity were significantly correlated with the changes in the visual field index (VFI), mean defect (MD), and P100 of the visual evoked potential. In the eyes with relatively stable BCVA and those with an obvious improvement in the BCVA, only the visual mean defect showed a significant change; the other indicators were not significantly different. Aside from the patients showing a tendency of spontaneous improvement, the others were in accordance with the requirement. The effects of Leber hereditary optical neuropathy (LHON) gene therapy should be evaluated primarily based on visual acuity. Additionally, visual field, neural fiber thickness, and electrophysiology should be considered in the evaluation.


Assuntos
Terapia Genética/métodos , Atrofia Óptica Hereditária de Leber/terapia , Retina/diagnóstico por imagem , Acuidade Visual , Adolescente , Adulto , Criança , Eletrorretinografia , Potenciais Evocados Visuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Óptica Hereditária de Leber/diagnóstico , Atrofia Óptica Hereditária de Leber/genética , Retina/fisiopatologia , Tomografia de Coerência Óptica , Campos Visuais , Adulto Jovem
8.
J Transl Med ; 14: 77, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26988982

RESUMO

BACKGROUND: Low back pain and sciatica caused by intervertebral disc (IVD) disease are associated with inflammatory responses. The cytokine interleukin 17 (IL-17) is elevated in herniated and degenerated IVD tissues and acts as a regulator of disc inflammation. The objective of this study was to investigate the involvement of IL-17A in IVD inflammatory response and to explore the mechanisms underlying this response. METHODS: Cells were isolated from nucleus pulposus (NP) tissues collected from patients undergoing surgeries for IVD degeneration. The concentrations of COX2 and PGE2, as well as of select proteins involved in the mitogen-activated protein kinase (MAPK)/activating protein-1 (AP-1) pathway, were quantified in NP cells after exposure to IL-17 with or without pretreatment with MAPK or AP-1 inhibitors. RESULTS: Our results showed that IL-17A increased COX2 expression and PGE2 production via the activation of MAPKs, including p38 kinase and Jun N-terminal kinase (JNK). Moreover, IL-17A-induced COX2 and PGE2 production was shown to rely on p38/c-Fos and JNK/c-Jun activation in an AP-1-dependent manner. CONCLUSION: In summary, our results indicate that IL-17A enhances COX2 expression and PGE2 production via the p38/c-Fos and JNK/c-Jun signalling pathways in NP cells to mediate IVD inflammation.


Assuntos
Inflamação/patologia , Interleucina-17/farmacologia , Disco Intervertebral/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Fator de Transcrição AP-1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Adulto , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
9.
Mater Sci Eng C Mater Biol Appl ; 60: 298-307, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706534

RESUMO

Avascular necrosis of the femoral head (ANFH) is difficult to treat due to high pressure and hypoxia, and reduced levels of growth factors such as bone morphogenetic protein (BMP), and vascular endothelial growth factor (VEGF). We generated a novel calcium phosphate (CPC) composite scaffold, which contains BMP-VEGF-loaded poly-lactic-co-glycolic acid (PLGA) microspheres (BMP-VEGF-PLGA-CPC). The BMP-VEGF-loaded microspheres have an encapsulation efficiency of 89.15% for BMP, and 78.55% for VEGF. The BMP-VEGF-PLGA-CPC scaffold also demonstrated a porosity of 62% with interconnected porous structures, and pore sizes of 219 µm and compressive strength of 6.60 MPa. Additionally, bone marrow mesenchymal stem cells (BMSCs) were seeded on scaffolds in vitro. Further characterization showed that the BMP-VEGF-PLGA-CPC scaffolds were biocompatible and enhanced osteogenesis and angiogenesis in vitro. Using a rabbit model of ANFH, BMP-VEGF-PLGA-CPC scaffolds were implanted into the bone tunnels of core decompression in the femoral head for 6 and 12 weeks. Radiographic and histological analysis demonstrated that the BMP-VEGF-PLGA-CPC scaffolds exhibited good biocompatibility, and osteogenic and angiogenic activity in vivo. These results indicate that the BMP-VEGF-PLGA-CPC scaffold may improve the therapeutic effect of core decompression surgery and be used as a treatment for ANFH.


Assuntos
Proteínas Morfogenéticas Ósseas/química , Proteínas Morfogenéticas Ósseas/uso terapêutico , Necrose da Cabeça do Fêmur/cirurgia , Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Animais , Materiais Biocompatíveis/química , Teste de Materiais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Alicerces Teciduais/química
11.
J Mol Histol ; 46(6): 475-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26446668

RESUMO

ADMATS-7 is known to play an important role in the pathogenesis of various diseases, including cartilaginous diseases. IL-17A is an inflammatory cytokine detected in degenerative disc tissues. However, the interplay between IL-17A and ADMATS-7 in human disc degeneration is still unknown. Samples collected from 50 patients were divided into three groups according to MRI degeneration grading system score. Immunohistochemistry, RT-PCR and western Blotting were used to investigate the expression of ADAMTS-7 in NP tissues. Furthermore, a rat disc degeneration model was established, and the expression level of ADAMTS-7 was assayed using immunohistochemistry, RT-PCR and western Blotting. The human NP cells were cultured in the presence and absence of IL-17A stimulation. RNA extracts were collected, and real-time PCR was performed to determine the expression of ADAMTS-7. Moreover, ADAMTS-7 concentrations were detected in human NP cell culture supernatants by ELISA. After culturing NP cells with IL-17A (with or without Etanercept), ADAMTS-7 levels were detected in each group. ADAMTS-7 expression was dramatically elevated in both human and rat degenerative NP tissues compared with normal controls. The RT-PCR and ELISA results revealed that IL-17A could enhance the production of ADAMTS-7, while ADAMTS-7 expression dramatically decreased in the IL-17A + Etanercept group in comparison to the IL-17A alone group. Our results indicate the presence of ADAMTS-7 in human NP cells and imply its potential role in disc degeneration. Additionally, our results indicate that IL-17A induced ADAMTS-7 expression via TNF-α, which may form a molecular axis in human NP cells.


Assuntos
Proteínas ADAM/genética , Expressão Gênica , Interleucina-17/metabolismo , Disco Intervertebral/citologia , Disco Intervertebral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas ADAM/metabolismo , Proteína ADAMTS7 , Adulto , Idoso , Animais , Modelos Animais de Doenças , Etanercepte/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Interleucina-17/farmacologia , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Adulto Jovem
12.
Sci Rep ; 5: 14036, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26358086

RESUMO

Genetic factors play an important role in the pathogenesis of diabetic retinopathy (DR). While many studies have focused on genes that increase susceptibility to DR, herein, we aimed to explore genes that confer DR resistance. Previously, we identified Hmg CoA reductase degradation protein 1 (SYVN1) as a putative DR protective gene via gene expression analysis. Transgenic mice overexpressing SYVN1 and wild-type (WT) mice with streptozotocin-induced diabetes were used in this experiment. Retinal damage and vascular leakage were investigated 6 months after induction of diabetes by histopathological and retinal cell apoptosis analyses and by retinal perfusion of fluorescein isothiocyanate-conjugated dextran. Compared with diabetic WT mice, diabetic SYVN1 mice had significantly more cells and reduced apoptosis in the retinal ganglion layer. Retinal vascular leakage was significantly lower in diabetic SYVN1 mice than in diabetic WT mice. The expression levels of endoplasmic reticulum (ER) stress-related, pro-inflammatory, and pro-angiogenic genes were also analyzed. Lower expression levels were observed in diabetic SYVN1 mice than in WT controls, suggesting that SYVN1 may play an important role in inhibiting ER stress, chronic inflammation, and vascular overgrowth associated with DR. Thus, these results strongly supported our hypothesis that SYVN1 confers DR resistance.


Assuntos
Retinopatia Diabética/genética , Predisposição Genética para Doença , Ubiquitina-Proteína Ligases/genética , Animais , Permeabilidade Capilar/genética , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Modelos Animais de Doenças , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Transgênicos , NF-kappa B/metabolismo , Retina/metabolismo , Retina/patologia , Vasos Retinianos/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Mediators Inflamm ; 2015: 196702, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25653475

RESUMO

ADAMTS-7 has been reported to exaggerate cartilage degeneration and to be associated with TNF-α and NF-κB signaling pathway. In this study we compared the expression of ADAMTS-7, TNF-α, and Phospho-NF-κB in patients with femoral neck fracture (FNF) and osteonecrosis of femoral head (ONFH) at different stages. We found that expression of ADAMTS-7, TNF-α, and Phospho-NF-κB was significantly upregulated in ONFH patients' articular cartilage and related to the pathogenesis of ONFH. Thus we conclude that ADAMTS-7 level appears to be positively associated with expression of TNF-α and Phospho-NF-κB P65 in cartilage, which may imply its association with cartilage destruction of ONFH.


Assuntos
Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Cartilagem/metabolismo , Cabeça do Fêmur/enzimologia , Regulação Enzimológica da Expressão Gênica , Osteonecrose/fisiopatologia , Fator de Transcrição RelA/metabolismo , Fatores de Necrose Tumoral/metabolismo , Proteína ADAMTS7 , Idoso , Idoso de 80 Anos ou mais , Feminino , Cabeça do Fêmur/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade
14.
PLoS One ; 9(10): e110993, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25343619

RESUMO

Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes.


Assuntos
Axônios/patologia , Células-Tronco Mesenquimais/metabolismo , Fatores de Crescimento Neural/metabolismo , Regeneração Nervosa/fisiologia , Recuperação de Função Fisiológica/fisiologia , Nervo Isquiático/lesões , Nervo Isquiático/fisiopatologia , Transdução Genética , Animais , Sobrevivência Celular , Colágeno/ultraestrutura , Dopamina/metabolismo , Citometria de Fluxo , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Neurônios Motores/patologia , Bainha de Mielina/metabolismo , Ratos Wistar , Nervo Isquiático/ultraestrutura , Caminhada
15.
Front Plant Sci ; 5: 702, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25566277

RESUMO

The embryo sac, the female gametophyte of flowering plants, plays important roles in the pollination and fertilization process. Maize (Zea mays L.) is a model monocot, but little is known about the interactions between its embryo sac and the pollen tube. In this study, we compared the transcript profiles of mature embryo sacs, mature embryo sacs 14-16 h after pollination, and mature nucelli. Comparing the transcript profiles of the embryo sacs before and after the entry of the pollen tube, we identified 3467 differentially expressed transcripts (3382 differentially expressed genes; DEGs). The DEGs were grouped into 22 functional categories. Among the DEGs, 221 genes were induced upon the entry of the pollen tube, and many of them encoded proteins involved in RNA binding, processing, and transcription, signaling, miscellaneous enzyme family processes, and lipid metabolism processes. Genes in the DEG dataset were grouped into 17 classes in a gene ontology enrichment analysis. The DEGs included many genes encoding proteins involved in protein amino acid phosphorylation and protein ubiquitination, implying that these processes might play important roles in the embryo sac-pollen tube interaction. Additionally, our analyses indicate that the expression of 112 genes encoding cysteine-rich proteins (CRPs) is induced during pollination and fertilization. The CRPs likely regulate pollen tube guidance and embryo sac development. These results provide important information on the genes involved in the embryo sac-pollen tube interaction in maize.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3309-14, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23427558

RESUMO

Two novel rare earth tungstosilicic polyoxometalate containing 5-fluorouracil, K26 (C4 H4 FN2O2)8Pr (SiW11 O39)4 x 10H2O (FPSW) and K26(C4H4FN2O2)8Sm(SiW11O39)4 x 9H2O (FSSW), were synthesized and their structure were characterized by using elemental analysis, FTIR spectra, X-ray powder diffraction and TG. The antitumor activity tests of the compounds FPSW and FSSW were carried out by the methyl thiazolyl tetrazolium method in hepatocellular carcinoma cell HepG-2. The results showed that FPSW and FSSW could inhibit the HepG-2 cells in vitro significantly. The EC50 of FPSW and FSSW is 1.94 x 10(-5) and 1.32 x 10(-5) mol x L(-1) respectively. The therapeutic index of FPSW and FSSW is 0.76 and 1.58 respectively.


Assuntos
Antineoplásicos/farmacologia , Fluoruracila/análise , Ácido Silícico/farmacologia , Compostos de Tungstênio/farmacologia , Fluoruracila/química , Células Hep G2 , Humanos , Metais Terras Raras/química , Ácido Silícico/química , Compostos de Tungstênio/química
17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 27(2): 126-9, 134, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19472870

RESUMO

OBJECTIVE: To study the change of the cracks and the influence on overall displacement of the cracked first mandibular molar under different loadings. METHODS: Three-dimensional finite element models of first mandibular molar with cracks of different depth and length and a control model with no crack were created firstly. Then six loading conditions were applied to the models simulating the real mastication. The changes of the cracks and displacement of the teeth under the six loadings conditions were obtained by finite element method. RESULTS: The length and depth of the cracks increased, the cracks of the occlusal surface become wider, and the crack was the widest under the fourth loading condition. Moreover, the edge of the cracks was irregular. The adjacent nodes were not in the same plane. The crack of the distal surface was the widest under the sixth loading condition. Compared to the teeth without cracks, the overall displacement of the teeth with cracks increased, but the increment was limited. CONCLUSION: The change of the cracks is closely related to the initial crack forms and loading conditions.


Assuntos
Análise do Estresse Dentário , Fraturas dos Dentes , Análise de Elementos Finitos , Humanos , Mastigação , Dente Molar , Dente
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