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1.
Kaohsiung J Med Sci ; 39(5): 478-488, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37098796

RESUMO

Ovarian cancer (OC) represents one of the most detrimental gynecological malignancies. RNA-binding protein eukaryotic translation initiation factor 4A isoform 3 (EIF4A3) is well-regarded as a definitive oncogene that contributes to the development of multiple malignant tumors. This study sought to elucidate the molecular mechanism of EIF4A3 in OC growth and aerobic glycolysis by regulation of pyruvate dehydrogenase kinase 4 (PDK4) mRNA stability. We determined the EIF4A3 and PDK4 expression levels in OC cell lines and normal ovarian epithelial cells, and subsequently evaluated the cell viability and colony formation by cell counting kit-8 and colony formation assays. The degree of cell aerobic glycolysis was evaluated by measurements of lactic acid production, glucose intake, adenosine triphosphate level, extracellular oxygen consumption, and protein levels of pyruvate kinase isozymes M2 and hexokinase-2. Afterwards, we verified the binding of EIF4A3 and PDK4 mRNA via RNA immunoprecipitation, and determined the mRNA stability after actinomycin D treatment. Finally, a series of rescue experiments was performed with pcDNA3.1-PDK4. EIF4A3 and PDK4 were upregulated in OC cells. Silencing EIF4A3 obstructed cell proliferation and aerobic glycolysis, while the same was annulled by EIF4A3 overexpression. Mechanically, EIF4A3 could bind to PDK4 mRNA to stabilize its mRNA and upregulate its protein levels. PDK4 overexpression inverted the inhibitory role of silencing EIF4A3 in proliferation and aerobic glycolysis. Overall, our findings highlighted that EIF4A3 induced OC progression by stabilizing PDK4 mRNA.


Assuntos
Fator de Iniciação 4A em Eucariotos , Glicólise , Neoplasias Ovarianas , Feminino , Humanos , Linhagem Celular Tumoral , Proliferação de Células , RNA Helicases DEAD-box , Neoplasias Ovarianas/genética , Fatores de Iniciação de Peptídeos , Isoformas de Proteínas , RNA Mensageiro/genética
2.
Neural Regen Res ; 18(3): 664-670, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36018192

RESUMO

Traumatic painful neuroma is an intractable clinical disease characterized by improper extracellular matrix (ECM) deposition around the injury site. Studies have shown that the microstructure of natural nerves provides a suitable microenvironment for the nerve end to avoid abnormal hyperplasia and neuroma formation. In this study, we used a decellularized nerve matrix scaffold (DNM-S) to prevent against the formation of painful neuroma after sciatic nerve transection in rats. Our results showed that the DNM-S effectively reduced abnormal deposition of ECM, guided the regeneration and orderly arrangement of axon, and decreased the density of regenerated axons. The epineurium-perilemma barrier prevented the invasion of vascular muscular scar tissue, greatly reduced the invasion of α-smooth muscle actin-positive myofibroblasts into nerve stumps, effectively inhibited scar formation, which guided nerve stumps to gradually transform into a benign tissue and reduced pain and autotomy behaviors in animals. These findings suggest that DNM-S-optimized neuroma microenvironment by ECM remodeling may be a promising strategy to prevent painful traumatic neuromas.

3.
Chinese Journal of School Health ; (12): 440-443, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-875716

RESUMO

Objective@#The influence of BMI and gender on Function Movement Screens (FMS) was analyzed to provide objective basis for improving physical quality and prevention of sports injuries among adolescents.@*Methods@#A total of 676 junior middle school students aged between 11 and 14 in grade 2 selected from a middle school in Beijing, were grouped by sex for FMS total score comparison. FMS scores of male and female students were compared according to body mass index (BMI). The 7 movements of FMS were compared and analyzed by male and female groups respectively. The influence of gender on FMS and the relationship between BMI and FMS were explored to seek the features of FMS in Chinese adolescents.@*Results@#FMS scores of male and female students in the BMI standard group were significantly higher than those of the super-recombination group(P<0.01); there was no significant difference in FMS scores between the standard group and the low weight group. BMI score was negatively correlated with FMS score, and the r value of boys was -0.27; for girls, the r value was -0.18(P<0.05). The total FMS score of male group was significantly lower than that of female group, which was (13.09±2.17) for male group and (13.91±1.79) for female group(t=-5.31, P<0.01). In comparison between men and women on each FMS test, there were significant differences in all categories except for the stability of trunk rotation (P<0.05).@*Conclusion@#Combined with BMI, FMS score can objectively reflect the overall athletic ability of adolescents. There were gender differences in FMS total score and individual score. FMS score can be used as a supplementary reference for physical fitness test of middle school students.

4.
Biochimie ; 167: 34-41, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491441

RESUMO

ArgR, a transcriptional regulator belonging to the AraC/XylS family, plays a key role in arginine metabolism regulation. ArgR has also been found to repress the transcription of a lipase gene, but its molecular mechanism is still unknown. In this study, we investigated the molecular mechanism acting on the expression of intracellular lipase gene lipA regulated by ArgR in Pseudomonas protegens Pf-5 through knockout and overexpression of argR, detection of DNA-protein interaction in vivo, determining whole-cell lipase activities of various strains derived from Pf-5, and examining ß-galactosidase activities of various lacZ fusions. The results demonstrated that ArgR inhibits lipA expression at the transcriptional level. Further results showed that the inhibition of lipA transcription by ArgR is mediated by binding to the ArgR binding site of lipA promoter to produce steric hindrance, in which the common sequence, TGTCGC is crucial for the ArgR binding. Besides, arginine inhibits lipA expression in both wild-type and argR mutant, and shows a synergistic inhibition on lipA expression when combined with ArgR. To the best of our knowledge, this is the first report on ArgR directly repressing the transcription of a lipase gene.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Regulação Bacteriana da Expressão Gênica , Pseudomonas/genética , Proteínas Repressoras/fisiologia , Arginina/metabolismo , Sítios de Ligação , Regiões Promotoras Genéticas , Proteínas Repressoras/genética
5.
Neural Regen Res ; 14(12): 2173-2182, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31397357

RESUMO

The intermingling of regenerated nerve fibers inside nerve grafts is the main reason for mismatched nerve fibers. This is one of the key factors affecting limb function recovery after nerve injury. Previous research has shown that the accuracy of axon regeneration can be improved by a bionic structural implant. To this aim, iodine and freeze-drying high-resolution micro-computed tomography was performed to visualize the 3D topography of the New Zealand rabbit sciatic nerve (25 mm). A series of 1-, 2-, 3-, and 4-custom anatomy-based nerve conduits (CANCs) were fabricated based on the anatomical structure of the nerve fascicle. The match index, luminal surface, and mechanical properties of CANCs were evaluated before implanting in a 10-mm gap of the sciatic nerve. Recovery was evaluated by histomorphometric analyses, electrophysiological study, gastrocnemius muscle weight recovery ratio, and behavioral assessments at 12 and 24 weeks postoperatively. The accuracy of nerve regeneration was determined by changes in fluorescence-labeled profile number during simultaneous retrograde tracing. Our results showed that the optimal preprocessing condition for high-resolution micro-computed tomography visualization was treatment of the sciatic nerve with 40% Lugol's solution for 3 days followed by lyophilization for 2 days. In vitro experiments demonstrated that the match index was highest in the 3-CANC group, followed by the 2-, 1-, and 4-CANC groups. The luminal surface was lowest in the 1-CANC group. Mechanical properties (transverse compressive and bending properties) were higher in the 3- and 4-CANC groups than in the 1-CANC group. In vivo experiments demonstrated that the recovery (morphology of regenerated fibers, compound muscle action potential, gastrocnemius muscle weight recovery ratio, pain-related autotomy behaviors, and range of motion) in the 3-CANC group was superior to the other CANC groups, and achieved the same therapeutic effect as the autograft. The simultaneous retrograde tracing results showed that the percentages of double-labeled profiles of the 2-, 3-, and 4-CANC groups were comparatively lower than that of the 1-CANC group, which indicates that regenerated nerve fascicles were less intermingled in the 2-, 3-, and 4-CANC groups. These findings demonstrate that the visualization of the rabbit sciatic nerve can be achieved by iodine and freeze-drying high-resolution micro-computed tomography, and that this method can be used to design CANCs with different channels that are based on the anatomical structure of the nerve. Compared with the 1-CANC, 3-CANC had a higher match index and luminal surface, and improved the accuracy of nerve regeneration by limiting the intermingling of the regenerated fascicles. All procedures were approved by the Animal Care and Use Committee, Xinjiang Medical University, China on April 4, 2017 (ethics approval No. IACUC20170315-02).

6.
Biomed Res Int ; 2019: 3845780, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31915690

RESUMO

OBJECTIVE: The use of a biofabrication nerve scaffold, which mimics the nerve microstructure, as an alternative for autologous nerve transplantation is a promising strategy for treating peripheral nerve defects. This study aimed to design a customized biofabrication scaffold model with the characteristics of human peripheral nerve fascicles. METHODS: We used Micro-MRI technique to obtain different nerve fascicles. A full-length 28 cm tibial nerve specimen was obtained and was divided into 14 two-centimetre nerve segments. 3D models of the nerve fascicles were obtained by three-dimensional reconstruction after image segmentation. The central line of the nerve fascicles was fitted, and the aggregation of nerve fascicles was analysed quantitatively. The nerve scaffold was designed by simulating the clinical nerve defect and extracting information from the acquired nerve fascicle data; the scaffold design was displayed by 3D printing to verify the accuracy of the model. RESULT: The microstructure of the sciatic nerve, tibial nerve, and common peroneal nerve in the nerve fascicles could be obtained by three-dimensional reconstruction. The number of cross fusions of tibial nerve fascicles from proximal end to distal end decreased gradually. By designing the nerve graft in accordance with the microstructure of the nerve fascicles, the 3D printed model demonstrated that the two ends of the nerve defect can be well matched. CONCLUSION: The microstructure of the nerve fascicles is complicated and changeable, and the spatial position of each nerve fascicle and the long segment of the nerve fascicle aggregation show great changes at different levels. Under the premise of the stability of the existing imaging techniques, a large number of scanning nerve samples can be used to set up a three-dimensional database of the peripheral nerve fascicle microstructure, integrating the gross imaging information, and provide a template for the design of the downstream nerve graft model.


Assuntos
Regeneração Nervosa/fisiologia , Nervos Periféricos/ultraestrutura , Engenharia Tecidual , Alicerces Teciduais , Humanos , Imageamento por Ressonância Magnética , Modelos Anatômicos , Nervos Periféricos/diagnóstico por imagem , Impressão Tridimensional , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
7.
Neural Regen Res ; 13(11): 1953-1960, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30233069

RESUMO

The most common methods for three-dimensional reconstruction of peripheral nerve fascicles include histological and radiology techniques. Histological techniques have many drawbacks including an enormous manual workload and poor image registration. Micro-magnetic resonance imaging (Micro-MRI), an emerging radiology technique, has been used to report results in the brain, liver and tumor tissues. However, micro-MRI usage for obtaining intraneural structures has not been reported. The aim of this study was to present a new imaging method for three-dimensional reconstruction of peripheral nerve fascicles by 1T micro-MRI. Freshly harvested sciatic nerve samples from an amputated limb were divided into four groups. Two different scanning conditions (Mannerist Solution/GD-DTPA contrast agent, distilled water) were selected, and both T1 and T2 phases programmed for each scanning condition. Three clinical surgeons evaluated the quality of the images via a standardized scale. Moreover, to analyze deformation of the two-dimensional image, the nerve diameter and total area of the micro-MRI images were compared after hematoxylin-eosin staining. The results show that rapid micro-MRI imaging method can be used for three-dimensional reconstruction of the fascicle structure. Nerve sample immersed in contrast agent (Mannerist Solution/GD-DTPA) and scanned in the T1 phase was the best. Moreover, the nerve sample was scanned freshly and can be recycled for other procedures. MRI images show better stability and smaller deformation compared with histological images. In conclusion, micro-MRI provides a feasible and rapid method for three-dimensional reconstruction of peripheral nerve fascicles, which can clearly show the internal structure of the peripheral nerve.

8.
Chinese Hospital Management ; (12): 10-13, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-706588

RESUMO

Objective To explore and establish the performance evaluation system for telemedicine in China.Methods By the method of literature and brainstorming,building evaluation model and the initial indicators,using Delphi method and Analytic Hierarchy Process to determine the index and its weight.Results Based on the PATH model,a telemedicine performance evaluation framework was established with five primary indicators,11 secondary indicators and 32 tertiary indicators.And the five primary indicators include patient-centered,medical effective and efficiency,staff-oriented,safety and response management.Conclusion The PATH model is suitable for the establishment of telemedicine performance evaluation framework.The patient-centered indicator has the highest weight,and the cost of telemedicine services should be controlled,and the patient satisfaction should be improved from all angles.

9.
Int J Surg ; 48: 53-58, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29017862

RESUMO

BACKGROUND/OBJECTIVES: Complex extremity trauma commonly involves both soft tissue and vascular injuries. Traditional two-stage surgical repair may delay rehabilitation and functional recovery, as well as increase the risk of infections. We report a single-stage reconstructive surgical method that repairs soft tissue defects and vascular injuries with flow-through free flaps to improve functional outcomes. METHODS: Between March 2010 and December 2016 in our hospital, 5 patients with severe upper extremity trauma received single-stage reconstructive surgery, in which a flow-through anterolateral thigh free flap was applied to repair soft tissue defects and vascular injuries simultaneously. Cases of injured artery were reconstructed with the distal trunk of the descending branch of the lateral circumflex femoral artery. A segment of adjacent vein was used if there was a second artery injury. Patients were followed to evaluate their functional recoveries, and received computed tomography angiography examinations to assess peripheral circulation. RESULTS: Two patients had post-operative thumb necrosis; one required amputation, and the other was healed after debridement and abdominal pedicle flap repair. The other 3 patients had no major complications (infection, necrosis) to the recipient or donor sites after surgery. All the patients had achieved satisfactory functional recovery by the end of the follow-up period. Computed tomography angiography showed adequate circulation in the peripheral vessels. CONCLUSIONS: The success of these cases shows that one-step reconstructive surgery with flow-through anterolateral thigh free flaps can be a safe and effective treatment option for patients with complex upper extremity trauma with soft tissue defects and vascular injuries.


Assuntos
Retalhos de Tecido Biológico/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Artéria Radial/lesões , Extremidade Superior/lesões , Lesões do Sistema Vascular/cirurgia , Pré-Escolar , Desbridamento , Tratamento de Emergência/métodos , Feminino , Artéria Femoral/cirurgia , Humanos , Artéria Ilíaca/cirurgia , Masculino , Pessoa de Meia-Idade , Necrose/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/cirurgia , Artéria Radial/transplante , Recuperação de Função Fisiológica , Lesões dos Tecidos Moles/etiologia , Lesões dos Tecidos Moles/cirurgia , Coxa da Perna/irrigação sanguínea , Coxa da Perna/cirurgia , Polegar/patologia , Polegar/cirurgia , Resultado do Tratamento , Extremidade Superior/cirurgia , Lesões do Sistema Vascular/etiologia , Adulto Jovem
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(6 Pt 1): 061703, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21797383

RESUMO

A recent study shows that the dipole elongation in the extended dipole model plays a significant role in the phase transitions of liquid crystal phases. In this paper, molecular dynamics (MD) simulations were performed for the dipole model with different distances between the two charges keeping the total dipole moment the same. The potential energy consists of the Lennard-Jones potential and the site-site electrostatic contribution of partial charges. Detailed analyses were made with respect to the average order parameters (P(1)) and (P(2)) as functions of density along with other thermodynamic properties. When the reduced dipole elongations are 0.16 and 0.32, respectively, it is shown that the chainlike structures in the low density regime, liquid phases with columnar and smectic orders, and solid phases are formed; the phase with nematic order is not present anymore. At 0.64, the phases with antiferroelectric order were favored. The transition is found at the reduced elongation 0.55. It shows that the phase transitions are quite sensitive to the molecular charge distribution; this simple system could exhibit rather rich phase behaviors, which represents a significant advance in identifying molecular and state parameters of the future ferroelectric liquids.


Assuntos
Hidrodinâmica , Simulação de Dinâmica Molecular , Conformação Molecular , Termodinâmica
11.
J Hazard Mater ; 177(1-3): 938-43, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20116171

RESUMO

Spherical 2-diazo-4,6-dinitrophenol (DDNP) with good flowability and controlled bulk density (0.65-0.95 g/cm(3)) has been prepared at factory scale by the modified method using 4-methylphenol as crystal control ingredient. Results showed that the yield of product was increased by 5-10%, and the waste water was significantly decreased due to circulation use of waste water compared with traditional method. Synthesized spherical DDNP was characterized by IR, laser granularity measurement, SEM, HPLC and XRD. IR spectrum confirmed the structural features of spherical DDNP. The particle analysis revealed that the modified method could offer spherical DDNP with average particle size of 350 microm and high purity (>98.52%). The XRD peaks of spherical DDNP have similar diffraction angles as those of traditional DDNP. The DSC profile of spherical DDNP showed the exothermic decomposition in the temperature range of 161.2-188.5 degrees C. The product can be pressed at over 40MPa without dead pressed phenomenon, and the minimum detonating charge of spherical DDNP was measured to be about 0.15g. Furthermore, impact sensitivity test suggested that spherical DDNP is less sensitive than traditional DDNP.


Assuntos
Dinitrofenóis/química , Substâncias Explosivas/química , Nitrocompostos/química , Dinitrofenóis/síntese química , Explosões , Substâncias Explosivas/síntese química , Conformação Molecular , Tamanho da Partícula , Temperatura , Termodinâmica
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(13): 3131-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14583288

RESUMO

A comparative study, luminescence behavior of 6-Mercaptopurine (6-MP), Azathiopurine (BAN), and 8-Azaguanine (8-Azan) have been investigated including the low temperature phosphorescence, the low temperature fluorescence, the room temperature phosphorescence (RTP) and the room temperature fluorescence (RTF). The effect of pH on the luminescence intensity is discussed. Analytical characteristics of RTF and RTP of 6-MP, BAN, and 8-Azan have been studied. The lifetime of phosphorescence and the polarity of RTF and RTP have been examined.


Assuntos
Azaguanina/química , Mercaptopurina/química , Concentração de Íons de Hidrogênio , Luminescência , Mercaptopurina/análogos & derivados , Espectrometria de Fluorescência/métodos , Espectrofotometria/métodos
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(7): 1469-76, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12714070

RESUMO

Paper substrate room temperature phosphorescence (RTP) of theobromine (TB), caffeine (CF) and theophylline (TP) were investigated. The method is based on fast speed quantitative filter paper as substrate and KI-NaAc as heavy atom perturber. Various factors affecting their RTP were discussed in detail. Under the optimum experimental conditions, the linear dynamic range, limit of detection (LOD), and relative standard deviation (R.S.D.) were 14.41 approximately 576.54 ng per spot, 1.14 ng per spot, 4.8% for TB, 5.44 approximately 699.08 ng per spot, 0.78 ng per spot, 1.56% for CF, 7.21 approximately 360.34 ng per spot, 1.80 ng per spot, 3.80% for TP, respectively. The first analytical application for the determination of these compounds was developed. The recovery of standard samples added to commercial products chocolate, tea, coffee and aminophylline is in the range 92.80-106.08%. The proposed method was successfully applied to real sample analysis without separation.


Assuntos
Cafeína/análise , Teobromina/análise , Teofilina/análise , Aminofilina/análise , Cacau/química , Café/química , Concentração de Íons de Hidrogênio , Luminescência , Metais Pesados , Papel , Espectrometria de Fluorescência , Chá/química , Temperatura
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