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4 results on '"Zheng-yu Zeng"'

1. Study on the Modification Technology of Zinc Powder in Inorganic Zinc-Rich Coating

Author

LIU Zheng-yu, ZENG Wei-min, MA Yu-lu

Subjects
inorganic zinc-rich coatings, flake zinc powder, modification, silane coupling agent, cerium nitrate, corrosion behavior, Materials of engineering and construction. Mechanics of materials, TA401-492, Technology
Abstract

In order to improve the shortcomings of poor dispersibility, easy agglomeration and easy corrosion of flaky zinc powder in inorganic zinc-rich coatings, the surface of flaky zinc powder was modified by silane coupling agent KH560 and cerium nitrate, and the optimum process conditions for surface modification of zinc powder was screened by polarization curve test.The changes in physical properties and corrosion resistance of zinc powder on zinc-rich coatings before and after modification were compared.Results showed that the optimal modification conditions of silane coupling agent KH560 were 12%(mass fraction), 60 ℃ of reaction temperature, pH 8 and 60 min of reaction time.The optimum dosage of cerium nitrate modified zinc flake/zinc powder was 0.01%(mass fraction)under the process conditions of room temperature, pH 7 and 60 min of reaction time.The dispersibility of modified zinc powder in water was improved.Moreover, the workability, drying time and adhesion of the modified zinc powder changed significantly.The corrosion current of the coating prepared by modified zinc powder was reduced by about 1 order of magnitude, the polarization resistance was increased by about 1 order of magnitude, and the corrosion resistance of the coating was significantly improved.In general, the cerium nitrate modified coating had the lowest passivation current and the smallest corrosion rate, which could be recommended to use cerium nitrate modified zinc powder for long-term protection.a

Published
2022
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2. Detection of α-globin gene deletion and duplication using quantitative multiplex PCR of short fluorescent fragments

Author

Gui Ling Mo, Wenli Feng, Yi Xin Zhan, Ya Juan Li, Zong Ping Mo, Zheng Yu Zeng, Chaohui Hu, Chang Shun Yu, and Wei Xi Cao

Subjects
Genetics, Biochemistry (medical), Clinical Biochemistry, DNA Mutational Analysis, Reproducibility of Results, General Medicine, Biology, Molecular biology, Polymerase Chain Reaction, law.invention, alpha-Globins, alpha-Thalassemia, law, hemic and lymphatic diseases, Gene Duplication, Gene duplication, Multiplex polymerase chain reaction, Multiplex, Copy-number variation, Multiplex ligation-dependent probe amplification, Allele, Gene, Polymerase chain reaction, Gene Deletion, Fluorescent Dyes
Abstract

Background The aim of this study was to establish a sensitive method that can detect the presence of not only the common but also the unusual or unknown α-globin gene deletions for screening of α-thalassemia. We used quantitative multiplex PCR of short fluorescent fragments (QMPSF) for the α-globin genes (HBA) to screen α-thalassemia deletions. Methods We set up and validated HBA-QMPSF using 50 negative and 100 positive controls of deletional α-thalassemia. To evaluate its ability to detect the presence of the common and unusual or unknown α-globin gene deletions, 579 unrelated samples were simultaneously analyzed using this assay and multiplex Gap polymerase chain reaction (Gap-PCR). The inconsistent results were further confirmed by multiplex ligation-dependent probe amplification (MLPA). Results HBA-QMPSF was capable of detecting α-globin gene deletions with an acceptable variability as shown by mean values (SD) of allele dosage for the heterozygous deleted control obtained from intra- and inter-experimental replicates [0.63 (0.01) and 0.61 (0.03)]. In 572 out of the 579 unrelated subjects, HBA-QMPSF and multiplex Gap-PCR gave consistent results. In seven cases which were finally proved to be composed of one rare deletion--Thai/-α3.7, one novel deletion--SEA/-α2.8, four αααanti3.7/αα and one αααanti4.2/αα triplications, HBA-QMPSF showed deletion or duplication in the α-globin gene while multiplex Gap-PCR failed to give the correct diagnosis. Conclusions HBA-QMPSF is able to detect the presence of the common and unusual or unknown α-thalassemia deletions and duplications. It can be used as an initial screening test for α-thalassemia caused by HBA gene copy number alteration.

Published
2011

3. [Beta-thalassemia major caused by compound heterozygosity for +40 to +43(-AAAC), IVS-2-654 (C to T) and codon 41/42 (-TCTT)]

Author

Zhao-hui, Hu, Yuan-li, Liu, Zheng-yu, Zeng, Xiao-lu, Zhang, and Qing-yi, Zhu

Subjects
Heterozygote, Haplotypes, Genetic Carrier Screening, DNA Mutational Analysis, Mutation, beta-Thalassemia, Humans, Nucleic Acid Hybridization, Female, Codon
Abstract

To report the analysis of a rare beta-thalassemia ternary heterozygote [+40 to +43(-AAAC)*CD41/42(-TTCT)*IVS-2-654] causing beta-thalassemia major in a Chinese.Using PCR-ASO probe hybridization analysis to scan 17 known types of beta-thalassemia mutations, and gene cloning and DNA sequencing to identify the underlying causative mutation.Reverse dot blot (RDB) analysis showed that the patient's beta-globin gene had three mutations: +40 to +43(-AAAC), CD41/42(-TCTT) and IVS-2-654(C to T). Beta-globin gene cloning and sequencing proved that, the two deletions of +40 to +43(-AAAC) and CD41/42(-TCTT) co-existed on the same chromosome, and the other homologous chromosome had an IVS-2-654 (C to T) mutation. So the patient is a compound heterozygote of [+40 to +43(-AAAC)*CD41/42 (-TCTT)]/IVS-2-654 (C to T) leading to beta-thalassemia major.The triple mutation of [+40 to +43(-AAAC)*CD41/42(-TCTT)/N] is a new genotype of beta-thalassemia in Chinese.

Published
2008

4. Nationwide prevalence of human papillomavirus infection and viral genotype distribution in 37 cities in China.

Author

Rong Wang, Xiao-lei Guo, Wisman, G. Bea. A., Schuuring, Ed, Wen-feng Wang, Zheng-yu Zeng, Hong Zhu, and Shang-wei Wu

Subjects
HIV infection epidemiology, DISEASE prevalence, DIAGNOSIS of HIV infections, TRANSMISSION of papillomavirus diseases, VIRUS diseases, GENE therapy
Abstract

Background: Type-specific high-risk HPV (hrHPV) infection is related to cervical carcinogenesis. The prevalence of hrHPV infection varies geographically, which might reflect the epidemiological characteristics of cervical cancer among different populations. To establish a foundation for HPV-based screening and vaccination programs in China, we investigated the most recent HPV prevalence and genotypic distributions in different female age groups and geographical regions in China. Methods: In 2012, a total of 120,772 liquid-based cytological samples from women enrolled for population- or employee-based cervical screening in 37 Chinese cities were obtained by the Laboratory of Molecular Infectious Diseases of Guangzhou KingMed. A total of 111,131 samples were tested by Hybrid Capture II and the other 9,641 were genotyped using the Tellgenplex™ HPV DNA Assay. Results: The total positive rate for hrHPV was 21.07 %, which ranged from 18.42 % (Nanchang) to 31.94 % (Haikou) and varied by region. The regions of Nanchang, Changsha, Hangzhou, Chengdu, Fuzhou, Guangdong, and Guiyang could be considered the low prevalence regions. Age-specific prevalence showed a "two-peak" pattern, with the youngest age group (15-19 years) presenting the highest hrHPV infection rate (30.55 %), followed by a second peak for the 50-60-year-old group. Overall, the most prevalent genotypes were HPV16 (4.82 %) and HPV52 (4.52 %), followed by HPV58 (2.74 %). Two genotypes HPV6 (4.01 %) and HPV11 (2.29 %) were predominant in the low-risk HPV (lrHPV) type, while the mixed genotypes HPV16 + 52 and HPV52 + 58 were most common in women with multiple infections. Conclusions: This study shows that HPV infection in China has increased to the level of an "HPV-heavy-burden" zone in certain regions, with prevalence varying significantly among different ages and regions. Data from this study represent the most current survey of the nationwide prevalence of HPV infection in China, and can serve as valuable reference to guide nationwide cervical cancer screening and HPV vaccination programs. [ABSTRACT FROM AUTHOR]

Published
2015
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