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1.
Appl Opt ; 63(1): 85-92, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175012

RESUMO

Optical probes are the preferred choice for high-precision surface metrology, necessitating improved flexibility and a broader range of motion to adapt to the increasing complexity of surfaces. This study introduces an interferometric probe designed for measuring aspheric surfaces, utilizing a wave-plate-array detection component. By integrating splitter elements into the detector, the probe improves integration and dynamic scanning performance, while maintaining high-precision measurement capability. The system design and working principle are explored, and comprehensive nonlinear models based on the Jones matrix theory are established. These models focus on the nonlinear errors arising from alignment errors in various cases. Moreover, rigorous numerical simulations and optical experiments are conducted to validate the proposed models. When the alignment error reaches 10°, it results in a maximum nonlinear error of 3.02 nm. The experimental results demonstrate the effectiveness of the models in capturing nonlinear errors induced by alignment errors, providing a theoretical foundation for error reduction and compensation.

2.
Opt Express ; 31(24): 39528-39545, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041272

RESUMO

In microscopic fringe projection profilometry (MFPP), the traditional absolute phase retrieval method using composite frequency fringe has the shortcomings of low accuracy and poor robustness due to mutual crosstalk of harmonic from the different channels of frequency-division multiplexing. In this study, an absolute phase retrieval method that avoids the inter-channel crosstalk is proposed. By introducing guard bands to accommodate the frequency channels corresponding to the second harmonic that dominate the high order harmonics, the aliasing between the second harmonic and the fundamental is eliminated. Consequently, phase maps without crosstalk can be demodulated using appropriate phase-shifting algorithms. The proposed method is well-suited for high-precision three-dimensional shape measurement scenarios in many fields such as integrated circuit manufacturing process control and micro-electro-mechanical system quality inspection. The experiment results demonstrate that the anti-crosstalk method is effective and can realize three-dimensional reconstruction for discontinuous planar surface and spherical surface.

3.
Appl Opt ; 61(8): 2036-2044, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35297896

RESUMO

As the electronic interconnection between chips, microbumps are crucial components in advanced packaging for the demand of better performance and higher packaging density. The height and coplanarity of microbumps are critical to ensure the reliability of connections. The poor uniformity in bump height will lead to disconnect or insufficient contact, which will directly result in the failure of the chip's function and a lower yield rate. In this paper, we proposed a height measurement method of microbumps using white-light triangulation combined with geometrical characteristics of bumps. A linear light projection module composed of a lens group and LED light source was set up as well as a high-quality imaging module consisting of a CCD camera and microscope objective group. The projection and imaging model of microbumps illuminated by the light plane at different positions during the scanning process was analyzed. The microbump height is computed from a simple formula based on the geometry of the specimen and the system configuration. The measurement results are compared with that obtained from a commercial optical profiler, and the measurement uncertainty is analyzed in detail.

4.
Pak J Med Sci ; 38(4Part-II): 872-877, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634603

RESUMO

Objective: To analyze the effects of carboplatin combined with paclitaxel-based intraperitoneal hyperthermic perfusion chemotherapy (IPCH) on serum levels of human epididymis protein 4 (HE4) and mitogen-dependent oncogene-1 (DJ-1) in patients with advanced recurrent ovarian cancer (OC). Methods: From July 2019 to July 2020, patients with advanced recurrent OC (n=92) treated in Affiliated Hospital of Hebei Engineering University were selected as study subjects. According to the random number table method, patients were divided into control group and observation group. Patients in the control group were treated with carboplatin combined with paclitaxel-based intravenous chemotherapy, and patients in the observation group were treated with carboplatin combined with paclitaxel-based IPCH. The therapeutic effects, serum levels of HE4, DJ-1 and human kallikrein 10 (HK-10), peripheral blood immune indexes and adverse reactions of patients were compared between the two groups. Results: The response rate of the observation group was significantly higher than that of the control group (p<0.05); after treatment, the indexes of HE4, DJ-1 and HK-10 in the two groups were significantly decreased, while the indexes of CD3+CD4+, CD3+CD56+ and CD3+CD4+/CD3+CD8+ were significantly increased; moreover, significantly lower indexes of HE4, DJ-1 and HK-10 and significantly higher indexes of CD3+CD4+, CD3+CD56+ and CD3+CD4+/CD3+CD8+ were found in the observation group when compared with the control group (p<0.05). The severity of myelosuppression, nausea and vomiting in the observation group was significantly lower than that in the control group, and the total tumor metastasis rate in the observation group was significantly lower than that in the control group (p<0.05). Conclusions: Carboplatin combined with paclitaxel IPCH had obvious inhibitory effects on HE4, DJ-1 and other serum tumor markers in patients with advanced recurrent OC, with a more prominent clinical effect, and could further significantly reduce the risk of adverse reactions and metastasis.

5.
Pak J Med Sci ; 38(6): 1508-1513, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991244

RESUMO

Objectives: To investigate the clinical effects of TP-based hyperthermic intraperitoneal chemotherapy (HIPEC) on the levels of antigen cluster protein 133 (CD133) and human epididymal secretory protein 4 (HE4) in patients with advanced epithelial ovarian cancer (EOC). Methods: A total of 104 patients with advanced EOC hospitalized in Affiliated Hospital of Hebei Engineering University from April 2015 to December 2018 were assigned to two groups using a random number table. A control group (n =52) treated by the conventional postoperative TP regimen and an observation group (n =52) receiving HIPEC in addition to the conventional postoperative TP regimen. CD133 and HE4 expression in serum, overall response rate (ORR), long-term efficacy, and incidence of drug toxicity were measured for comparative analysis. Results: The serum levels of CD133 and HE4 expression in the observation group were lower than in the control group (P < 0.005, respectively); the observation group surpassed the control group in ORR, 2-year survival, and progression-free survival (PFS) (P < 0.005, respectively); however, the two groups had no statistically significant difference in the incidence of drug toxicity (P > 0.05). Conclusions: TP-based HIPEC can effectively inhibit CD133 and HE4 expression in advanced EOC, which thereby improves the clinical efficacy and encourages longer survival.

6.
Plant Cell Environ ; 43(5): 1148-1159, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31833568

RESUMO

Inorganic phosphorus (Pi) deficiency induces anthocyanin accumulation in the leaves of some plant species; however, the molecular mechanisms underlying this phenomenon have not been well characterized. Here, we showed that microRNA399d (miR399d), high-affinity Pi transporter McPHT1;4, and McMYB10 are strongly induced in Malus leaves suffering from Pi deficiency. By culturing explants of transiently transformed plants in MS medium under conditions of Pi sufficiency and Pi deficiency, miR399d and McPHT1;4 were shown to play essential roles in the response to Pi deficiency and to play positive roles in the regulation of anthocyanin biosynthesis. Silencing of McHDA6 expression and treatment with the inhibitor trichostatin A suggested that the low expression of McHDA6 simultaneously reduced the transcription of McMET1 and decreased the methylation level of the McMYB10 promoter; however, the expression of McMYB10 and anthocyanin content were increased. Bimolecular fluorescence complementation and yeast two-hybrid assays revealed that McHDA6 binds directly to McMET1 through its BAH2 and DNMT1-RFD domains. Based on the results of our study, we propose a mechanism for the molecular regulation of anthocyanin biosynthesis, namely, the miR399d and epigenetic modification comodulation model, to explain the phenomenon in which leaves turn red under conditions of Pi deficiency.


Assuntos
Antocianinas/metabolismo , Epigênese Genética , Malus/metabolismo , MicroRNAs/metabolismo , Fósforo/deficiência , Folhas de Planta/metabolismo , RNA de Plantas/metabolismo , Cromatografia Líquida de Alta Pressão , Regulação da Expressão Gênica de Plantas/genética , Inativação Gênica , MicroRNAs/fisiologia , RNA de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Técnicas do Sistema de Duplo-Híbrido
7.
Appl Opt ; 55(1): 110-6, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26835629

RESUMO

A high-speed high-resolution heterodyne interferometer using a laser with low beat frequency is developed. The interferometer has two spatially separated parallel beams with different frequencies. Two interference signals with opposite Doppler shift are optically generated by the interferometric optics. The measurement electronics uses two identical phasemeters for the two opposite interference signals. The two interference signals are selectively used according to the speed of the target, which makes sure that the Doppler shift of the selected signal is always positive, so that the measurable speed is no longer limited by the beat frequency of the laser source. Experimental results show that the measurement resolution is 0.62 nm. The measurable speed can exceed the restriction determined by the beat frequency. Compared with a commercial interferometer, the displacement difference is less than 40 nm in a travel range of 900 mm.

8.
Opt Express ; 23(11): 14360-79, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26072800

RESUMO

A general method is presented for spherical surface testing with unknown phase shifts based on a physical model of the interferometer cavity, which describes the phase shifts taking into account the rigid cavity motions and the radial imaging distortion of the interferometer. The captured interferograms are processed frame by frame with the regularized frequency-stabilizing method, so as to get the phase shifts between the frames. These phase shift data are subsequently fitted, and the initial estimations for the wavefront, direct current and interference contrast terms are calculated by the least-squares method. Specially, a simple way is proposed to find reasonable initial guess for numerical aperture (NA) of the test beam (when NA is unknown), so as to ensure the effectiveness of the above phase shift fitting procedure. Then, the wavefront result is further refined in an iterative way, by fitting the sequence of interferograms to the physical model of the interferometer cavity with the linear regression technique. Finally, the wavefront result related to the actual surface profile is retrieved after removing the aberrations due to the surface misalignment and the imaging distortion. Both simulations and experiments with the ZYGO interferometer have been carried out to validate the proposed method, with experimental accuracies better than 0.004λ RMS achieved. The proposed method provides a feasible way to spherical surface testing without the use of any phase-shifting devices, while retaining good accuracy and robust convergence performance.

9.
Plant Direct ; 7(7): e513, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37484545

RESUMO

The increasing ground-level ozone (O3) pollution resulting from rapid global urbanization and industrialization has negative effects on many plants. Nonetheless, many gaps remain in our knowledge of how ornamental plants respond to O3. Rose (Rosa hybrida L.) is a commercially important ornamental plant worldwide. In this study, we exposed four rose cultivars ("Schloss Mannheim," "Iceberg," "Lüye," and "Spectra") to either unfiltered ambient air (NF), unfiltered ambient air plus 40 ppb O3 (NF40), or unfiltered ambient air plus 80 ppb O3 (NF80). Only the cultivar "Schloss Mannheim" showed significant O3-related effects, including foliar injury, reduced chlorophyll content, reduced net photosynthetic rate, reduced stomatal conductance, and reduced stomatal apertures. In "Schloss Mannheim," several transcription factor genes-HSF, WRKY, and MYB genes-were upregulated by O3 exposure, and their expression was correlated with that of NCED1, PP2Cs, PYR/PYL, and UGTs, which are related to ABA biosynthesis and signaling. These results suggest that HSF, WRKY, and MYB transcription factors and ABA are important components of the plant response to O3 stress, suggesting a possible strategy for cultivating O3-tolerant rose varieties.

10.
Luminescence ; 26(6): 592-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21374792

RESUMO

A novel method was developed using capillary electrophoresis (CE) coupled with tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence (ECL) for highly sensitive detection of metformin hydrochloride (MH) derivatizatized with acetaldehyde. The precolumn derivatization of MH with acetaldehyde was performed in phosphate buffer solution (0.3 mol/L, pH 7.5) at room temperature for 120 min. The effects of acetaldehyde concentration, buffer pH, electrokinetic voltage and injection time were investigated. Under optimized detection conditions, the MH ECL detection sensitivity was more than 120 times that without derivatization. The linear concentration range for MH was 0.001-15.00 µg/mL (with a correlation coefficient of 0.9992). The detection limit was 0.31 ng/mL with a signal:noise ratio of 3. The recoveries of MH in human urine were in the range 98.50-99.72%. Copyright © 2011 John Wiley & Sons, Ltd.


Assuntos
Acetaldeído/química , Eletroforese Capilar/métodos , Hipoglicemiantes/análise , Metformina/análise , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Luminescência , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
11.
Genes (Basel) ; 12(9)2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34573419

RESUMO

Somatic embryogenesis is an effective tool for the production of forest tree seedlings with desirable characteristics; however, the low initiation frequency and productivity of high-quality mature somatic embryos are still limiting factors for Larix kaempferi (Japanese larch). Here, we analyzed the expression pattern of L. kaempferi cyclin-dependent kinase B 1;2 (LaCDKB1;2) during somatic embryogenesis in L. kaempferi and its relationship with the cell proliferation rate. We also analyzed the effect of LaCDKB1;2 over-expression on somatic embryo quality. The results revealed a positive correlation between LaCDKB1;2 expression and the cell proliferation rate during the proliferation stage. After LaCDKB1;2 over-expression, the proliferation rate of cultures increased, and the number of somatic embryos in transgenic cultures was 2.69 times that in non-transformed cultures. Notably, the number of normal cotyledonary embryos in transgenic cultures was 3 times that in non-transformed cultures, indicating that LaCDKB1;2 not only increases the proliferation of cultures and the number of somatic embryos but also improves the quality of somatic embryos. These results provide insight into the regulatory mechanisms of somatic embryogenesis as well as new Larix breeding material.


Assuntos
Cotilédone/crescimento & desenvolvimento , Larix/genética , Proteínas de Plantas/genética , Técnicas de Embriogênese Somática de Plantas/métodos , Ácido Abscísico/farmacologia , Proliferação de Células , Cotilédone/efeitos dos fármacos , Cotilédone/genética , Quinases Ciclina-Dependentes/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Larix/citologia , Filogenia , Melhoramento Vegetal/métodos , Células Vegetais , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas
12.
Polymers (Basel) ; 13(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808408

RESUMO

The dissolution and molecular interactions of cellulose carbamate (CC) in NaOH/ZnO aqueous solutions were studied using optical microscopy, differential scanning calorimetry (DSC), 1H NMR, dynamic light scattering (DLS), atomic force microscopy (AFM), transmission electron microscopy (TEM), and molecular dynamic simulation. The dissolution of CC in NaOH/ZnO aqueous solutions using the freezing-thawing method was an exothermic process, and the lower temperature was favorable for the dissolution of CC. ZnO dissolved in NaOH aqueous solutions with the formation of Zn(OH)42-, and no free Zn2+ ions existed in the solvents. NaOH/Na2Zn(OH)4 system formed strong interactions with the hydroxyl groups of CC to improve its solubility and the stability of CC solution. The results indicate that 7 wt% NaOH/1.6 wt% ZnO aqueous solution was the most appropriate solvent for the dissolution of CC. This work revealed the dissolution interaction of CC-NaOH/ZnO solutions, which is beneficial for the industrialization of the CarbaCell process.

13.
Tree Physiol ; 41(10): 1918-1937, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-33847364

RESUMO

Dormancy release and reactivation of temperate-zone trees involve the temperature-modulated expression of cell-cycle genes. However, information on the detailed regulatory mechanism is limited. Here, we compared the transcriptomes of the stems of active and dormant larch trees, emphasizing the expression patterns of cell-cycle genes and transcription factors and assessed their relationships and responses to temperatures. Twelve cell-cycle genes and 31 transcription factors were strongly expressed in the active stage. Promoter analysis suggested that these 12 genes might be regulated by transcription factors from 10 families. Altogether, 73 cases of regulation between 16 transcription factors and 12 cell-cycle genes were predicted, while the regulatory interactions between LaMYB20 and LaCYCB1;1, and LaRAV1 and LaCDKB1;3 were confirmed by yeast one-hybrid and dual-luciferase assays. Last, we found that LaRAV1 and LaCDKB1;3 had almost the same expression patterns during dormancy release and reactivation induced naturally or artificially by temperature, indicating that the LaRAV1-LaCDKB1;3 module functions in the temperature-modulated dormancy release and reactivation of larch trees. These results provide new insights into the link between temperature and cell-cycle gene expression, helping to understand the temperature control of tree growth and development in the context of climate change.


Assuntos
Regulação da Expressão Gênica de Plantas , Larix , Larix/metabolismo , Dormência de Plantas , Temperatura , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
14.
Carbohydr Polym ; 242: 116420, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32564827

RESUMO

A dual physically crosslinking (DPC) strategy is used to construct hydrogels with ultrahigh strength. First, polyelectrolyte complex (PEC) hydrogels were prepared through in situ polymerization of acrylic acid monomers in chitosan solutions. Subsequently, cations and anions were introduced into the PEC hydrogels to form strong electrostatic interactions with the polymer chains. The mechanical properties of the DPC hydrogels strongly depended on the ionic concentration and the valence state of the loading ions. The tensile strength of DPC-Na 8-20-2.0, DPC-Mg 8-20-2.0, DPCAl 8-20-2.0 and DPC-Sul 8-20-0.8 reached to 2.36, 12.59, 65.1 and 2.80 MPa, respectively, which were significantly higher than that of PEC 8-20 (0.29 MPa). Moreover, DPC-Na, DPC-Mg and DPC-Sul still maintained a good flexibility. Specifically, hydrogels of DPC-Ca exhibited ionic conductivity and freeze tolerance, which could be cooled to -20 °C without freezing. The DPC strategy opens an avenue to fabricate hydrogels with outstanding mechanical properties.


Assuntos
Resinas Acrílicas/química , Quitosana/química , Reagentes de Ligações Cruzadas/química , Congelamento , Hidrogéis/química , Condutividade Elétrica , Tamanho da Partícula , Propriedades de Superfície , Resistência à Tração
15.
J Mater Chem B ; 8(27): 5921-5927, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32542300

RESUMO

Hydrogel-based multifunctional materials have attracted much attention. In this work, novel mineralized hydrogels were fabricated through physically cross-linked polyvinylpyrrolidone (PVP) and CaCO3. The mineralized hydrogels were prepared by simply mixing CaCl2, Na2CO3, and PVP in aqueous solutions. The CO32- induced the aggregation of the PVP chains and the CaCO3 particles in situ generated in the aqueous solution worked as fillers to strengthen the hydrogels. Based on this method, other kinds of mineralized hydrogels were prepared by replacing the Ca2+ with different metal ions. The mineralized hydrogels displayed shapeable, self-healing and thixotropic properties. Moreover, the mineralized hydrogel-based sensor showed good and stable sensitivity to compressive pressure, and could be used to monitor human actions. This work presents a facile method for preparing mineralized hydrogels, which are promising for various applications due to their outstanding properties.


Assuntos
Hidrogéis/química , Minerais/química , Povidona/química , Cicatrização/efeitos dos fármacos , Carbonato de Cálcio/química , Cloreto de Cálcio/química , Carbonatos/química , Cátions Bivalentes/química , Bandagens Compressivas , Força Compressiva , Reagentes de Ligações Cruzadas/química , Humanos , Hidrogéis/metabolismo , Povidona/metabolismo , Reologia
16.
ACS Appl Mater Interfaces ; 11(7): 7510-7521, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30676717

RESUMO

A solid surface morphology is of great importance for the fundamental research in the field of hydrophobic materials. Commercial sand core funnels (SCs) are embedded with multilevel pore size and surface roughness, which are excellent models to study the mechanism of surface wettability. This article described a simple, green, and facile method to fabricate hydrophobic surfaces on SCs via reacting with perfluorooctyltriethoxysilane (PFTS) vapor. Systematic analyses on the reaction, properties, and applications of the PFTS-modified SCs were conducted, which involved the reaction time and temperature, water resistance, mechanical durability, self-cleaning test, surface adhesion, and underoil superhydrophobicity. The water contact angle of the modified SCs increased with a decrease of the pore size and an increase of the surface roughness of the sand core particles. The wettability of the modified SCs agrees well with the intermediate states between Wenzel and Cassie-Baxter. The PFTS-modified SCs retained excellent chemical stability in rigid conditions and good mechanical properties. The hydrophobic SCs showed oil/water separation performance with excellent efficiency, reusability, and high flux. Especially for the PFTS-modified SCs with small pore sizes, water-in-oil emulsion separation was successfully realized. The easily accessible, relatively cheap raw materials and facile process in this work are very desirable to obtain a specific wetting surface, which will offer promising applications in various fields.

17.
J Pharm Biomed Anal ; 48(4): 1249-53, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18976877

RESUMO

A novel and sensitive method for the determination of amoxicillin (AM) in human urine has been established using capillary electrophoresis (CE) coupled with electrochemiluminescence (ECL) detection, based on the ECL enhancement of Tris(2,2'-bipyridyl) ruthenium(II) with AM. The effects of several factors such as the detection potential, the concentration and the pH of phosphate buffer, the electrokinetic voltage and the injection time were investigated. Under the optimal conditions, the linear concentration of AM ranged from 1.0 ng/ml to 8.0 microg/ml (with a correlation coefficient of 0.9999). The limit of detection was 0.31 ng/ml. The mean recovery was 95.77% with relative standard deviations of no larger than 2.2%. This method is quick (the total run time within 6 min). This method has been successfully applied to a pharmacokinetic study in human urine after oral administration of AM.


Assuntos
Amoxicilina/farmacocinética , Amoxicilina/urina , Antibacterianos/farmacocinética , Antibacterianos/urina , Eletroforese Capilar/métodos , Medições Luminescentes/métodos , Sistemas On-Line , 2,2'-Dipiridil/química , Soluções Tampão , Calibragem , Eletroquímica , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Fosfatos/química , Reprodutibilidade dos Testes , Rutênio/química
18.
Front Plant Sci ; 9: 704, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29915606

RESUMO

In higher plants, anthocyanins are protective secondary metabolites, which contribute to the color of leaves, stems, flowers, and fruits, and have been found to have an antioxidant role in human health. In this study, we determined the expression of McMYB10 and its specific E3 ubiquitin ligase, McCOP1, in crabapple leaves during the course of a day and in five leaf development stages. Interestingly, the results showed that the transcription level of McCOP1 genes was higher in daylight than at night, and the transcripts of McMYB10 presented a positive correlation with the transcription of McCOP1-1 and McCOP1-2 and anthocyanin accumulation in a crabapple cultivar with red-colored leaves. Several MYB transcription factor (TF) binding sites of the MYBCORE type were found in the McCOP1-1 and McCOP1-2 promoters, and we deduced that there may be a relationship between McMYB10 and McCOP1-1 and McCOP1-2 at the transcriptional level. Yeast one hybrid (Y1H) and electrophoretic mobility shift assays (EMSA) demonstrated that the McMYB10 TF binds specifically to the promoter of McCOP1-1 and McCOP1-2. Furthermore, increased levels of McMYB10 promoted anthocyanin biosynthesis and the expression level of McCOP1-1 and McCOP1-2 in crabapple leaves during continuous light treatments, and overexpression or silencing of McMYB10 in crabapple leaves and apple fruits also result in an increase or decrease, respectively, in the expression of McCOP1-1 and McCOP1-2 and in anthocyanin biosynthesis. Our results reveal a new self-regulation mechanism in where McMYB10 modulates its own expression by activating McCOP1-1 and McCOP1-2 expression to promote ubiquitination of the McMYB10 protein by McCOP1.

19.
Artigo em Inglês | MEDLINE | ID: mdl-17652036

RESUMO

A fast and sensitive approach for determination of erythromycin in rat plasma was described. The method used capillary electrophoresis coupled with end-column electrochemiluminescence (ECL) detection of Ru(bpy)(3)(2+). The separation column used had an inner diameter of 75 microm. The running buffer was 15 mmol/L sodium phosphate (pH=7.5). The solution in the detection cell was 50 mmol/L sodium phosphate (pH=8.0) and 5 mmol/L Ru(bpy)(3)(2+). ECL intensity varied linearly with erythromycin concentration from 1.0 ng/mL to 10 microg/mL. The detection limit (S/N=3) was 0.35 ng/mL. The relative standard deviations, of ECL intensity and migration time for eight consecutive injections of 1.0 microg/mL erythromycin (n=8), were 1.3% and 1.8%, respectively. The method was successfully applied to erythromycin determination in rat plasma. The recovery ranged from 92.5 to 97.5%.


Assuntos
Antibacterianos/sangue , Eletroforese Capilar/métodos , Eritromicina/sangue , Medições Luminescentes/instrumentação , Compostos Organometálicos/sangue , Compostos Organometálicos/química , Animais , Coleta de Amostras Sanguíneas/métodos , Soluções Tampão , Calibragem , Eletroquímica , Injeções Intravenosas , Medições Luminescentes/métodos , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Artigo em Inglês | MEDLINE | ID: mdl-17928277

RESUMO

A novel determination method for josamycin (JOS) based on capillary electrophoresis-electrochemiluminescence detection has been described. In this study, platinum disk electrode (300 microm in diameter) was used as a working electrode and the conditions affecting separation and detection were investigated in detail. Under optimal condition: 40 cm separation capillary (75 microm i.d.); 1.25 V applied potential on the Pt disc of the ECL detector cell; 5 mM Ru(bpy)3(2+) and 50mM phosphate buffer (pH 7.5) in the detection cell; 12 kV separation voltage; 8s injection time; 10 kV injection voltage and 15 mM running buffer (pH 7.5), calibration curve was linear over the range from 10 ng/mL to 5.0 microg/mL with a detection limit of 3.1 ng/mL at a signal-to-noise ratio of 3. The method can be successfully applied for the determination of josamycin in rat plasma in 6 min and the extraction recoveries with spiked plasma samples were over 92%.


Assuntos
Antibacterianos/sangue , Eletroquímica/métodos , Eletroforese Capilar/métodos , Josamicina/sangue , Medições Luminescentes/métodos , Animais , Concentração de Íons de Hidrogênio , Compostos Organometálicos/química , Ratos , Reprodutibilidade dos Testes
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