1.Determination of Content and Related Substances of Amlodipine Besylate Tablets by HPLC
China Pharmacist 2014;(12):2046-2050
Objective:To establish an HPLC method compatible with the mass spectrometry for the determination of the content and related substances in amlodipine besylate tablets. Methods:The sample was separated on a CAPCELL PAK C18 column (250 mm × 4. 6 mm, 5 μm) with the mobile phase consisting of methanol and 20 mmol·L-1 ammonium acetate (60∶40) at a flow rate of 1. 0 ml·min-1 . The detection wavelength was set at 237 nm. The column temperature was 35℃ and the injection volume was 20 μl. Be-sides, an HPLC-QTOF MS method was used to identify the molecular structure of the related substances of amlodipine. Results: The related substances were completely separated from amlodipine. The linear range of amlodipine besylate was 10-100 μg · ml-1 ( r =0. 999 8), and the mean recovery was 99. 2%(RSD=1. 0%,n=9). The main related substances could be detected by HPLC-QTOF MS. Conclusion:The established method is accurate, reliable and reproducible, which can be used in the quality control of amlodip-ine besylate tablets.
2.A Monte Carlo model of light propagation in human brain edema based on the visible Chinese human datasets
International Journal of Biomedical Engineering 2018;41(2):111-117
Objective To investigate the non-invasive monitoring method of cerebral edema and the combination of cerebral edema and intracranial hemorrhage (ICH) based on fNIRS. Methods A head model was established based on the visible Chinese human (VCH) datasheet. The Monte Carlo simulation was conducted to analyze the light intensity, light absorption, photon fluence and spatial sensitivity distribution of head models at different levels of cerebral edema. The change in light intensity caused by ICH was also studied. Results Light intensity is directly related to the increase in cerebrospinal fluid volume. Photons can be transmitted to brain tissue. The occurrence of ICH can significantly reduce light intensity and can be used to reflect the presence of ICH in cerebrospinal fluid. Conclusion The use of fNIRS technology to observe changes in light intensity is expected to be a simple and reliable bedside monitoring method for cerebral edema.
3.Analysis of viral nucleic acid and cytokines in 12 children with 2019-nCoV infection
Xufang LI ; Chunxiao FANG ; Huamei YANG ; Minxia CHEN ; Lanhui SHE ; Yu GONG ; Fansen ZENG ; Jiawei YE ; Limei TAN ; Qian ZHONG ; Lingli LIU ; Yanling WANG ; Yi XU
Chinese Journal of Microbiology and Immunology 2020;40(8):574-578
Objective:To analyze the viral nucleic acid and cytokines in 12 children with 2019-nCoV infection.Methods:Clinical and laboratory data of the children diagnosed with 2019-nCoV infection in Guangzhou Women and Children′s Medical Center from January to April 2020 were retrospectively analyzed. Throat and anal swabs were collected on alternate days for the detection of 2019-nCoV nucleic acid by fluorescence quantitative PCR. Flow cytometry was used to detect serum cytokines including IFN-γ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-17F, IL-22, TNF-α and TNF-β during the early (both throat and anal swab tests were positive), the intermediate (throat swab test was negative, while anal swab test remained positive), and the convalescence (both throat and anal swab tests were negative) stages of infection.Results:A total of 12 children were enrolled in this study. The male-to-female ratio was 5∶1. The average age was (7.0±4.3) years. There were two asymptomatic, five mild and five common cases. No severe or critical cases were involved. Initially, throat and anal swab nucleic acid tests were simultaneously positive in nine children newly diagnosed in our hospital and the median time of viral shedding in throat swab was longer than that in throat swab [32 (4.5, 45.0) d vs 3 (2, 9) d, Z=11.0, P=0.010]. The median difference of viral shedding time between anal swab and pharyngeal swab was 25.5 (1.5, 42.8) d. The overall levels of serum cytokines IL-17A, IL -4 and IL-5 in different stages of the disease (early, intermediate and convalescence stage) were statistically different ( Z or F, P values were 8.33, 0.016; 5.36, 0.010 and 6.56, 0.004, respectively), and a significant increase was observed in the intermediate stage of infection. IL-17F, IL-2 and IL-22 were all increased during the infection, but there was no significant statistical difference among the three stages ( P>0.05). Conclusions:It was noted that intestinal viral shedding needed a longer time. Although the infectivity has not been determined, higher requirements have been put forward for disease prevention and control. Cytokines secreted by Th2 and Th17 cells were involved in the immune response in children with non-severe 2019-nCoV infection. Monitoring viral shedding and cytokine changes in pediatric patients would be conducive to disease assessment.
4.Identification of the core promoter of the pmel gene of Bashang long-tail chickens.
Xiaohui LIU ; Rongyan ZHOU ; Yongdong PENG ; Chuansheng ZHANG ; Lanhui LI ; Xianglong LI
Chinese Journal of Biotechnology 2018;34(11):1750-1759
To explore the activity of the pmel core promoter of Bashang long-tail chickens, we constructed dual-luciferase expression vectors and transiently transfected into DF1 cells with Lipofectamine 2000. We measured the luciferase activity with the dual-luciferase detection kit. The 1 268 bp fragment in 5-flanking region of the pmel gene in Bashang long-tail chickens was cloned. The region from -1 200 bp to +68 bp included 2 CpG islands and multiple transcription factor binding sites. We constructed 9 expression vectors with different promoter regions and a mutant vector of the core promoter region of the pmel gene of Bashang long-tail chickens. The core promoter region from -840 bp to +68 bp was identified in the pmel gene. The region from -590 to -525 bp negatively regulated the pmel gene during the transcription process. The -840--590 bp and -525--266 bp regions were positive regulatory regions. The polymorphic sites (-456, -435, -410, -374 and -341) had a significant effect on the promoter activity of the pmel gene.
Animals
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Chickens
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genetics
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Cloning, Molecular
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CpG Islands
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Luciferases
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Promoter Regions, Genetic
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gp100 Melanoma Antigen
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genetics