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1.
BMC Plant Biol ; 24(1): 653, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987678

RESUMEN

BACKGROUND: Walnut anthracnose caused by Colletotrichum gloeosporioides seriously endangers the yield and quality of walnut, and has now become a catastrophic disease in the walnut industry. Therefore, understanding both pathogen invasion mechanisms and host response processes is crucial to defense against C. gloeosporioides infection. RESULTS: Here, we investigated the mechanisms of interaction between walnut fruits (anthracnose-resistant F26 fruit bracts and anthracnose-susceptible F423 fruit bracts) and C. gloeosporioides at three infection time points (24hpi, 48hpi, and 72hpi) using a high-resolution time series dual transcriptomic analysis, characterizing the arms race between walnut and C. gloeosporioides. A total of 20,780 and 6670 differentially expressed genes (DEGs) were identified in walnut and C. gloeosporioides against 24hpi, respectively. Generous DEGs in walnut exhibited opposite expression patterns between F26 and F423, which indicated that different resistant materials exhibited different transcriptional responses to C. gloeosporioides during the infection process. KEGG functional enrichment analysis indicated that F26 displayed a broader response to C. gloeosporioides than F423. Meanwhile, the functional analysis of the C. gloeosporioides transcriptome was conducted and found that PHI, SignalP, CAZy, TCDB genes, the Fungal Zn (2)-Cys (6) binuclear cluster domain (PF00172.19) and the Cytochrome P450 (PF00067.23) were largely prominent in F26 fruit. These results suggested that C. gloeosporioides secreted some type of effector proteins in walnut fruit and appeared a different behavior based on the developmental stage of the walnut. CONCLUSIONS: Our present results shed light on the arms race process by which C. gloeosporioides attacked host and walnut against pathogen infection, laying the foundation for the green prevention of walnut anthracnose.


Asunto(s)
Colletotrichum , Juglans , Enfermedades de las Plantas , Juglans/microbiología , Juglans/genética , Colletotrichum/fisiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , RNA-Seq , Frutas/microbiología , Frutas/genética , Transcriptoma , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno/genética , Resistencia a la Enfermedad/genética
2.
Bioorg Chem ; 150: 107493, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38870703

RESUMEN

2. This research investigates the impact of the EGCG-CSH/n-HA/CMC composite material on bone defect repair, emphasizing its influence on macrophage polarization and osteogenic differentiation of BMSCs. Comprehensive evaluations of the composite's physical and chemical characteristics were performed. BMSC response to the material was tested in vitro for proliferation, migration, and osteogenic potential. An SD rat model was employed for in vivo assessments of bone repair efficacy. Both transcriptional and proteomic analyses were utilized to delineate the mechanisms influencing macrophage behavior and stem cell differentiation. The material maintained excellent structural integrity and significantly promoted BMSC functions critical to bone healing. In vivo results confirmed accelerated bone repair, and molecular analysis highlighted the role of macrophage M2 polarization, particularly through changes in the SIRPA gene and protein expression. EGCG-CSH/n-HA/CMC plays a significant role in enhancing bone repair, with implications for macrophage and BMSC function. Our findings suggest that targeting SIRPA may offer new therapeutic opportunities for bone regeneration.

3.
Neurosurg Rev ; 47(1): 328, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39004661

RESUMEN

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: The purpose of this study is to investigate whether the removal of the posterior longitudinal ligament (PLL) affects the mid-term outcome of anterior cervical fusion for cervical spondylosis with sympathetic symptoms(CSSS). METHODS: From January 2012 to July 2013, 66 patients who were diagnosed with CSSS with ≥ 10-year follow-up at our institution were assessed. All patients were divided into two groups: Group A (36 cases) in which patients underwent anterior cervical fusion with PLL resection and Group B (30 cases) in which patients underwent anterior cervical fusion without PLL resection. The sympathetic symptom 20-point system was used to evaluate the sympathetic symptoms, such as tinnitus, headache and vertigo, etc. And the neurological status was assessed by the Japanese Orthopedic Association (JOA) scores. Clinical and radiologic data were evaluated preoperatively, 9 days, 3 months, 6 months, 12 months, 24 months, 60 months, and 120 months postoperatively. Data collected included all perioperative complications as morbidities that occurred during the period of follow-up. RESULTS: The postoperative JOA scores and 20-point score can be significantly improved compared with preoperative whether the PLL is removed in both groups. However, the postoperative 20-point score of patients in group A was significantly different from that in group B. No loosening and displacement of prosthesis occurred. CONCLUSION: A better clinical effect could be attained when resecting the PLL in the operation. The PLL may play an important role in CSSS. The mid-term outcomes of anterior cervical fusion with PLL resection were satisfied in treating CSSS.


Asunto(s)
Vértebras Cervicales , Ligamentos Longitudinales , Fusión Vertebral , Espondilosis , Humanos , Masculino , Femenino , Espondilosis/cirugía , Espondilosis/complicaciones , Persona de Mediana Edad , Fusión Vertebral/métodos , Estudios Retrospectivos , Vértebras Cervicales/cirugía , Resultado del Tratamiento , Anciano , Ligamentos Longitudinales/cirugía , Adulto , Estudios de Cohortes , Estudios de Seguimiento
4.
Plant J ; 111(4): 1152-1166, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35765867

RESUMEN

Walnut (Juglans regia L.) anthracnose, induced by Colletotrichum gloeosporioides, is a catastrophic disease impacting the walnut industry in China. Although WRKY transcription factors play a key role in plant immunity, the function of the WRKY gene family in walnut resistance to C. gloeosporioides is not clear. Here, through transcriptome sequencing and quantitative real-time polymerase chain reaction (qRT-PCR), we identified a differentially expressed gene, JrWRKY21, that was significantly upregulated upon C. gloeosporioides infection in walnut. JrWRKY21 positively regulated walnut resistance to C. gloeosporioides, as demonstrated by virus-induced gene silencing and transient gene overexpression. Additionally, JrWRKY21 directly interacted with the transcriptional activator of the pathogenesis-related (PR) gene JrPTI5L in vitro and in vivo, and could bind to the W-box in the JrPTI5L promoter for transcriptional activation. Moreover, JrPTI5L could induce the expression of the PR gene JrPR5L through binding to the GCCGAC motif in the promoter. Our data support that JrWRKY21 can indirectly activate the expression of the JrPR5L gene via the WRKY21-PTI5L protein complex to promote resistance against C. gloeosporioides in walnut. The results will enhance our understanding of the mechanism behind walnut disease resistance and facilitate the genetic improvement of walnut by molecular breeding for anthracnose-resistant varieties.


Asunto(s)
Colletotrichum , Juglans , Colletotrichum/genética , Resistencia a la Enfermedad/genética , Juglans/genética , Enfermedades de las Plantas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
Opt Express ; 31(22): 36314-36326, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017786

RESUMEN

The intensity coupling characteristics of Ne dual-isotope inflation and dual-longitudinal-mode operation ring lasers were investigated based on the Lamb theory. Considering the contribution of the Ne isotope system to the polarization of the gain medium and gain saturation effects, the frequency coupling effects were analyzed. Combined with the plasma dispersion function, the optical cavity length is 0.47 m, Ne20: Ne22= 0.53:0.47; the frequency spacing of the adjacent longitudinal mode is 640 MHz, and the intensity tuning curve of the ring laser is simulated. The alterations in the gain self-saturation and mutual saturation coefficients between the four frequencies generated via dual-longitudinal mode splitting are comprehensively discussed. Finally, a detection experiment for the intensity-tuning curve is designed to verify the theoretical analysis.

6.
Sensors (Basel) ; 23(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36991932

RESUMEN

Frequency-difference-stabilized dual-frequency solid-state lasers with tunable and large frequency difference have become an ideal light source for the high-accuracy absolute-distance interferometric system due to their stable multistage synthetic wavelengths. In this work, the advances in research on oscillation principles and key technologies of the different kinds of dual-frequency solid-state lasers are reviewed, including birefringent dual-frequency solid-state lasers, biaxial and two-cavity dual-frequency solid-state lasers. The system composition, operating principle, and some main experimental results are briefly introduced. Several typical frequency-difference stabilizing systems for dual-frequency solid-state lasers are introduced and analyzed. The main development trends of research on dual-frequency solid-state lasers are predicted.

7.
Sensors (Basel) ; 22(16)2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-36016061

RESUMEN

In order to stabilize the self-biasing state of a laser gyroscope, a dual-longitudinal-mode asymmetric frequency stabilization technique was studied. The special frequency stabilization is based on the accurate control of the intensity tuning curve in the prism ring laser. In this study, the effects of the ratio of the Ne isotopes, the inflation pressure, and the frequencies coupling on the intensity tuning curve in a laser gyro were examined. The profiles of the intensity tuning curve were simulated under the mixing ratios of Ne20 and Ne22 of 1:1 and 7:3, and the inflation pressures were 350 Pa, 400 Pa, and 450 Pa. The mixing ratio of Ne20 and Ne27 was dealt with similarly. The method for precisely adjusting the profiles of the intensity tuning curve was analyzed. The profiles were verified by experiments under different isotope ratios and pressures. Finally, based on a prism ring laser with an optical length of 0.47 m, the proposed frequency stabilization method was preliminarily verified.

8.
Molecules ; 27(14)2022 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-35889286

RESUMEN

Poly(p-phenylene terephthalamide) (PPTA) is one kind of lyotropic liquid crystal polymer. Kevlar fibers performed from PPTA are widely used in many fields due to their superior mechanical properties resulting from their highly oriented macromolecular structure. However, the "infusible and insoluble" characteristic of PPTA gives rise to its poor processability, which limits its scope of application. The strong interactions and orientation characteristic of aromatic amide segments make PPTA attractive in the field of self-assembly. Chemical derivation has proved an effective way to modify the molecular structure of PPTA to improve its solubility and amphiphilicity, which resulted in different liquid crystal behaviors or supramolecular aggregates, but the modification of PPTA is usually complex and difficult. Alternatively, higher-order all-PPTA structures have also been realized through the controllable hierarchical self-assembly of PPTA from the polymerization process to the formation of macroscopic products. This review briefly summarizes the self-assembly methods of PPTA-based materials in recent years, and focuses on the polymerization-induced PPTA nanofibers which can be further fabricated into different macroscopic architectures when other self-assembly methods are combined. This monomer-started hierarchical self-assembly strategy evokes the feasible processing of PPTA, and enriches the diversity of product, which is expected to be expanded to other liquid crystal polymers.

9.
BMC Plant Biol ; 21(1): 249, 2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34059002

RESUMEN

BACKGROUND: Walnut anthracnose induced by Colletotrichum gloeosporioides is a disastrous disease affecting walnut production. The resistance of walnut fruit to C. gloeosporioides is a highly complicated and genetically programmed process. However, the underlying mechanisms have not yet been elucidated. RESULTS: To understand the molecular mechanism underlying the defense of walnut to C. gloeosporioides, we used RNA sequencing and label-free quantitation technologies to generate transcriptomic and proteomic profiles of tissues at various lifestyle transitions of C. gloeosporioides, including 0 hpi, pathological tissues at 24 hpi, 48 hpi, and 72 hpi, and distal uninoculated tissues at 120 hpi, in anthracnose-resistant F26 fruit bracts and anthracnose-susceptible F423 fruit bracts, which were defined through scanning electron microscopy. A total of 21,798 differentially expressed genes (DEGs) and 1929 differentially expressed proteins (DEPs) were identified in F26 vs. F423 at five time points, and the numbers of DEGs and DEPs were significantly higher in the early infection stage. Using pairwise comparisons and weighted gene co-expression network analysis of the transcriptome, we identified two modules significantly related to disease resistance and nine hub genes in the transcription expression gene networks. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of the DEGs and DEPs revealed that many genes were mainly related to immune response, plant hormone signal transduction, and secondary metabolites, and many DEPs were involved in carbon metabolism and photosynthesis. Correlation analysis between the transcriptome data and proteome data also showed that the consistency of the differential expression of the mRNA and corresponding proteins was relatively higher in the early stage of infection. CONCLUSIONS: Collectively, these results help elucidate the molecular response of walnut fruit to C. gloeosporioides and provide a basis for the genetic improvement of walnut disease resistance.


Asunto(s)
Colletotrichum , Juglans/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Frutas/genética , Frutas/microbiología , Juglans/genética , Proteoma , Transcriptoma
10.
Appl Opt ; 60(36): 11066-11074, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-35201095

RESUMEN

When measuring the form deviation of the gear tooth flank with laser interferometry, due to the limitation of the depth of field of the lens, focused and defocused regions exist in the interferogram simultaneously. The introduced errors that were generated by these defocused regions decrease the measurement accuracy. Therefore, the evaluation of definition for interferograms is necessary for image processing. However, the gradient of gray, which performs by fringes, makes it difficult for traditional algorithms to evaluate its definition. This paper proposes a method based on nonsubsampled contourlet transformation (NSCT) combined with fringe direction as weighting coefficients to solve the problem. First, the information about the directions of these fringes in interferograms was evaluated. Then, the NSCT method was applied to interferograms so that several sub-images in different scales and directions can be achieved. Based on these sub-images and directions information, an improved function for definition evaluation was conducted. Lastly, a series of simulations and experiments was carried out to verify its feasibility and accuracy.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Interferometría
11.
Soft Matter ; 16(15): 3705-3716, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32232287

RESUMEN

This study examines nonlinear rheological responses to uniaxial extension of two entangled polystyrene (PS) solutions and two PS melts. Several unusual characteristics are revealed. The pair of the PS solutions have the same number of entanglements per chain (because of the same concentration) but well separated effective glass transition temperatures Tg. When examined at a common effective rate of extension (e.g., the same Rouse-Weissenberg number WiR) and at a comparable distance from their respective Tg, the solution A with lower Tg, examined at a lower temperature, shows stronger stress responses when WiR > 1. At the same test temperature and a common WiR, the solution A is still found to display a stronger stress response than the solution B that is made of the same fraction of parent PS in a second solvent also made of oligomeric PS of higher molecular weight. Finally, there are two features intrinsic to each of the four PS samples. First, at the same WiR they show reduced stress level at a lower temperature. Second, at sufficiently high applied Hencky rates, they show limiting rate behavior, i.e., undergoing the same melt rupture independent of the applied rate. These remarkable rheological responses indicate major theoretical difficulties facing the subject of nonlinear extensional rheology of entangled polymers.

12.
J Chem Phys ; 151(12): 124906, 2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31575207

RESUMEN

Fast deformation of entangled melts is known to cause chain stretching due to affinelike straining of the entanglement network. Since the chain deformation may also result in perturbations of covalent bond angles and bond length, there are always possible enthalpic effects. In this study, we first subject polystyrene and PMMA of different molecular weights to either uniaxial melt extension or planar extension and subsequently impose rapid thermal quenching to preserve the chain deformation. Then, such pre-melt-deformed samples are annealed at various temperatures below the glass transition temperature Tg. During annealing, these samples can undergo appreciable contraction on a time scale much shorter than the alpha relaxation time. Significant retractive stress is observed when such contracting samples are held fixed during the annealing. The stress level can be nearly as high as the Cauchy stress produced during melt stretching. These observations not only allowed us to investigate glassy chain dynamics as well as the molecular nature of mechanical stress but may also suggest that pre-melt-stretched polymers can cause segmental mobilization in the glassy state. The available evidence indicates that the retractive stress is enthalpic in origin, associated with the conformational distortion at the bond level produced by melt stretching.

13.
Opt Express ; 26(24): 32353-32364, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30650696

RESUMEN

This study experimentally reveals the self-biasing phenomenon in prism laser gyros. When the gyro operates in a specific double longitudinal mode and four-frequency oscillation state, the gyro can detect the normal angular velocity component of the Earth's rotation without dithering, the self-biasing status is induced. In this study, a laboratory platform of the self-biasing laser gyro is established. The two longitudinal modes oscillate on both sides of the gain curve. The intensity ratio of the strong and weak modes is about 1.4 to 1, and the coupling effects of these two modes with parallel linear polarization have been discussed using Lamb theory. Because the adverse effects of biasing technical are avoided, the self-biasing gyro has potential to challenge the strategic precision.

14.
Phys Rev Lett ; 120(7): 077801, 2018 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-29542983

RESUMEN

New experiments show that tensile stress vanishes shortly after preyield deformation of polymer glasses while tensile stress after postyield deformation stays high and relaxes on much longer time scales, thus hinting at a specific molecular origin of stress in ductile cold drawing: chain tension rather than intersegmental interactions. Molecular dynamics simulation based on a coarse-grained model for polystyrene confirms the conclusion that the chain network plays an essential role, causing the glassy state to yield and to respond with a high level of intrachain retractive stress. This identification sheds light on the future development regarding an improved theoretical account for molecular mechanics of polymer glasses and the molecular design of stronger polymeric materials to enhance their mechanical performance.

16.
Molecules ; 23(9)2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-30231526

RESUMEN

A previous study showed that intravenous immunoglobulin (IVIG) could preserve higher levels of biologically active lactone moieties of topotecan, 7-ethyl-10-hydroxycamptothecin (SN-38) and 10-hydroxycamptothecin at physiological pH 7.40. As one of camptothecin analogues (CPTs), the interaction of 7-ethylcamptothecin and IVIG was studied in vitro in this study. It was shown that the main binding mode of IVIG to 7-ethylcamptothecin was hydrophobic interaction and hydrogen bonding, which is a non-specific and spontaneous interaction. The hydrophobic antigen-binding cavity of IgG would enwrap the drug into a host-guest inclusion complex and prevent hydrolysis of the encapsulated drug, while the drug is adjacent to the chromophores of IgG and may exchange energy with chromophores and quench the fluorescence of the protein. Also, the typical ß-sheet structure of IVIG unfolded partially after binding to 7-ethylcamptothecin. Additionally, the binding properties of IVIG and six CPTs with different substituents at A-ring and/or B-ring including camptothecin, topotecan, irinotecan, 10-hydroxycamptothecin, 7-ethylcamptothecin and SN-38 were collected together and compared each other. Synergizing with anti-cancer drugs, IVIG could be used as a transporter protein for 7-ethylcamptothecin and other CPTs, allowing clinicians to devise new treatment protocols for patients.


Asunto(s)
Camptotecina/análogos & derivados , Inmunoglobulinas Intravenosas/química , Camptotecina/química , Camptotecina/metabolismo , Humanos , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Inmunoglobulina G/química , Inmunoglobulina G/metabolismo , Inmunoglobulinas Intravenosas/metabolismo , Inmunoglobulinas Intravenosas/farmacocinética , Cinética , Modelos Moleculares , Conformación Molecular , Unión Proteica , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
17.
Can J Microbiol ; 62(4): 287-95, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26974503

RESUMEN

Since the 1970s, several dsRNA viruses, including Radish yellow edge virus, Raphanus sativus virus 1, Raphanus sativus virus 2, and Raphanus sativus virus 3, have been identified and reported as infecting radish. In the present study, in conjunction with a survey of seed-borne viruses in cultivated Brassica and Raphanus using the dsRNA diagnostic method, we discovered 3 novel cryptoviruses that infect Brassica and Raphanus: Raphanus sativus partitivirus 1, which infects radish (Raphanus sativus); Sinapis alba cryptic virus 1, which infects Sinapis alba; and Brassica rapa cryptic virus 1 (BrCV1), which infects Brassica rapa. The genomic organization of these cryptoviruses was analyzed and characterized. BrCV1 might represent the first plant partitivirus found in Gammapartitivirus. Additionally, the evolutionary relationships among all of the partitiviruses reported in Raphanus and Brassica were analyzed.


Asunto(s)
Brassica rapa/virología , Virus de Plantas/genética , Virus ARN/genética , Raphanus/virología , Semillas/virología , Genoma Viral , Tipificación Molecular , Filogenia , ARN Bicatenario/genética , ARN Viral/genética , Análisis de Secuencia de ADN
18.
Biotechnol Appl Biochem ; 62(3): 309-15, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25066911

RESUMEN

Glucagon-like peptide-1 (GLP-1) plays an important role in the regulation of postprandial insulin release. Here, we used the split DnaB mini-intein system to produce recombinant human GLP-1/7-36 (rhGLP-1) in Escherichia coli. The C-terminal domain of DnaB mini-intein (IntC) was genetically fused at the N-terminus of rhGLP-1 to produce IntC-GLP-1. IntC-GLP-1 and N-terminal domain of DnaB mini-intein (IntN) protein were prepared in a denatured buffer of pH 8.0. IntC-GLP-1 was diluted 1:8 into the phosphate buffer of pH 6.6. IntN was added into the diluted solution of IntC-GLP-1 at the molar ratio of 1:2. Then, rhGLP-1 was released from IntC-GLP-1 via inducible C-terminal peptide-bond cleavage by shifting pH from 8.0 to 6.6 at 25 °C for 24-H incubation. Then, the supernatant was applied to a Ni-Sepharose column, and the pass through fraction was collected. About 5.34 mg of rhGLP-1 with the purity of 97% was obtained from 1 L of culture medium. Mass spectrometry showed the molecular weight of 3,300.45 Da, which was equal to the theoretical value of GLP-1/7-36. The glucose-lowering activity of rhGLP-1 was confirmed by the glucose tolerance test in mice. In conclusion, the reported method was an efficient strategy to produce rhGLP-1 without using enzyme or chemical reagents, which could also be used for other similar peptides.


Asunto(s)
Clonación Molecular/métodos , AdnB Helicasas/genética , Péptido 1 Similar al Glucagón/metabolismo , Inteínas/genética , Proteínas Recombinantes de Fusión/metabolismo , Escherichia coli/genética , Péptido 1 Similar al Glucagón/química , Péptido 1 Similar al Glucagón/genética , Péptido 1 Similar al Glucagón/aislamiento & purificación , Humanos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación
19.
Calcif Tissue Int ; 95(2): 153-65, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24907907

RESUMEN

The investigation of agents for the treatment of osteoporosis has been a long-standing effort. The Wnt pathway plays an important role in bone formation and regeneration, and expression of Wnt pathway inhibitors, Dickkopf-1 (DKK1), appears to be associated with changes in bone mass. Inactivation of DKK1 leads to substantially increased bone mass in genetically manipulated animals. DKK1-derived peptides (DDPs) were added to BMP2-stimulated MC3T3-E1 preosteoblastic cells in vitro to evaluate inhibitory activity of DDPs in MC3T3-E1 cell differentiation. Study was extended in vivo on old female mice to show whether or not inhibition of endogenous DKK1 biological activity using DDPs vaccination approach leads to increase of bone formation, bone density, and improvement of bone microstructure. We reported that synthetic DDPs were able to reduce alkaline phosphatase activity, prevent mineralization and inhibit the differentiation of MC3T3-E1 cells in vitro. Furthermore, vaccination with these DDPs in aged female mice 4 times for a total period of 22 weeks promoted bone mass and bone microstructure. 3D microCT and histomorphometric analysis showed that there were significant increase in bone mineral densities, improvement of bone microstructure and promotion of bone formation in the vaccinated mice, especially in the mice vaccinated with DDP-A and DDP-C. Histological and scanning electron microscopy image analysis also indicated that vaccination increased trabecular bone mass and significantly decreased fragmentation of bone fibers. Taken together, these preclinical results suggest that vaccination with DDPs represents a promising new therapeutic approach for the treatment of bone-related disorders, such as osteoporosis.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/inmunología , Osteogénesis/fisiología , Osteoporosis/prevención & control , Vacunas/farmacología , Absorciometría de Fotón , Envejecimiento , Animales , Western Blotting , Modelos Animales de Enfermedad , Femenino , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Osteoporosis/metabolismo , Péptidos/inmunología , Vacunación , Microtomografía por Rayos X
20.
Appl Microbiol Biotechnol ; 98(1): 105-14, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24113827

RESUMEN

A murine monoclonal antibody (mAb) 3C7 against integrin αIIbß3 was previously obtained as a potential antithrombotic agent in our laboratory. The epitope of 3C7 is a specific conformation of the αIIbß3 complex, but not either of the two subunits, which makes it different from abciximab, a supplementary antibody drug used in percutaneous coronary intervention which has a cross-reaction with other integrins sharing the ß3 subunit. To reduce the human anti-mouse antibody reactions of 3C7, the variable regions of this antibody were cloned and fused with the constant counterparts of human IgG1. Two vectors of light and heavy chains were constructed and co-transfected into CHO-dhfr(-) cells. The chimeric antibody c3C7 was purified and the properties of c3C7 were compared with 3C7. Identical to its parent antibody 3C7, c3C7 binds to the αIIbß3 complex, but not to either of the subunits. The K(d) value of c3C7 was in the same order of magnitude as 3C7 (1.570 ± 0.326 vs 0.780 ± 0.182 nmol/L). Human platelet aggregation induced by adenosine diphosphate was effectively inhibited by c3C7 in a dose-dependent manner. In conclusion, after the modification, c3C7 retained the properties of its parent mAb with no loss of its biological activity. Therefore, c3C7 has the potential to become a novel agent for the treatment of thrombosis.


Asunto(s)
Anticuerpos/genética , Anticuerpos/inmunología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/inmunología , Animales , Anticuerpos/aislamiento & purificación , Células CHO , Cricetinae , Cricetulus , Humanos , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Inmunoglobulina G/aislamiento & purificación , Ratones , Agregación Plaquetaria/efectos de los fármacos , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo
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