18 results on '"Chen, Xianmei"'
Search Results
2. Progress in the research on radiation-induced defects in nanomaterials
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GAN Pingping, CHEN Xianmei, JIANG Zhiwen, WANG Yunlong, and MA Jun
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radiation-induced defects ,nanomaterials ,2d materials ,porous materials ,radiation damage ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Radiation-induced defects in nanomaterials are an important aspect of the research on the effects of radiation on materials. Recently, the research on radiation-induced defects in semiconductor materials, low-dimensional materials, and high-specific-surface porous materials has become a new application of radiation technology. Radiation-induced nanomaterial defect engineering has the potential to be used to improve the electromagnetic, catalytic, adsorption, and mechanical properties of nanomaterials and will play an important role in materials science, electronic-device development, catalysis, and environmental science. Therefore, this review presents the recent progress and state-of-art in the formation and tuning mechanism of radiation-induced defects in nanomaterials and provides a direction for future development.
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- 2022
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3. Reusable Shape‐Memory Photonic Crystal Paper for Pin‐Printing and High‐Resolution Press Printing.
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Chen, Xianmei, Wang, Zhihao, Tang, Mingshuo, He, Zhiwei, Yu, Miao, Yu, Tianran, Cai, Jian, Emer, Hanayxam, Ma, Jun, and Wang, Yunlong
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PHOTONIC crystals ,ELECTRONIC paper ,PRINTING presses ,SHAPE memory polymers ,PRICE marks ,PRINTING industry - Abstract
Rewritable photonic crystal (PC) paper has the potential to significantly reduce the consumption of forest resources in the printing industry, while also being environmentally friendly and efficient. However, traditional PC papers based on solvent or photothermal responses can lead to diffusion, which can hinder printing accuracy. In this study, a novel rewritable PC paper compatible with pin‐printing is presented based on a pressure‐responsive shape‐memory PC paper. High‐resolution printing can be realized by both computer‐programmed 3D‐printed seals and pin‐printing techniques. The information written on this PC rewritable paper can be erased by water, enabling the paper to be rewritten and reused at least 8 times without any change in performance. Furthermore, the information stored on the PC paper is stable and can be stored in ordinary environments for at least 6 months without fading. The PC paper has the capability of multicolor printing with a precision finer than 100 μm and has potential in office papers, smart price tags, and anti‐counterfeiting labels. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Be aware of the effects of glucocorticoids on SIADH: A case report
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Li, Huaqian, Huang, Lijun, Wu, Ge, Chen, Xianmei, Zheng, Qiaoan, Su, Faming, Liang, Maoshan, and Chen, Xiaoming
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- 2019
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5. Characteristics of phenotypic antibiotic resistance of Helicobacter pylori and its correlation with genotypic antibiotic resistance: A retrospective study in Ningxia.
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Hu, Shengjuan, Zhou, Yan, Deng, Yanhong, Bo, Yang, Chen, Xianmei, Yang, Wei, Shi, Ruichun, Zhao, Wei, Hou, Zhanbing, Hu, Jianping, Liu, Jianguo, Zhang, Xilong, Yong, Heli, Wang, Ping, Li, Fei, Qi, Hailong, Wang, Xiaoyun, Jin, Lijuan, Cui, Ting, and Yong, Haijiang
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DRUG resistance in bacteria ,HELICOBACTER pylori ,GENOTYPES ,DISC diffusion tests (Microbiology) ,PHENOTYPES ,GASTRIC mucosa - Abstract
Background: Geographic differences exist in the antibiotic resistance patterns of Helicobacter pylori. Personalized treatment regimens based on local or individual resistance data are essential. We evaluated the current status of H. pylori resistance in Ningxia, analyzed resistance‐related factors, and assessed the concordance of phenotypic and genotypic resistance. Methods: Strains were isolated from the gastric mucosa of patients infected with H. pylori in Ningxia and relevant clinical information was collected. Phenotypic antibiotic susceptibility assays (Kirby–Bauer disk diffusion) and antibiotic resistance gene detection (Sanger sequencing) were performed. Results: We isolated 1955 H. pylori strains. The resistance rates of H. pylori to amoxicillin, levofloxacin, clarithromycin, and metronidazole were 0.9%, 42.4%, 40.4%, and 94.2%, respectively. Only five tetracycline‐resistant and one furazolidone‐resistant strain were identified. Overall, 3.3% of the strains were sensitive to all six antibiotics. Multidrug‐resistant strains accounted for 22.9%, of which less than 20% were from Wuzhong. Strains isolated from women and patients with nonulcerative disease had higher rates of resistance to levofloxacin and clarithromycin. Higher rates of resistance to metronidazole, levofloxacin, and clarithromycin were observed in the older age group than in the younger age group. The kappa coefficients of phenotypic resistance and genotypic resistance for levofloxacin and clarithromycin were 0.830 and 0.809, respectively, whereas the remaining antibiotics showed poor agreement. Conclusion: H. pylori antibiotic resistance is severe in Ningxia. Therefore, furazolidone, amoxicillin, and tetracycline are better choices for the empirical therapy of H. pylori infection in this region. Host sex, age, and the presence of ulcerative diseases may affect antibiotic resistance of the bacteria. Personalized therapy based on genetic testing for levofloxacin and clarithromycin resistance may be a future direction for the eradication therapy of H. pylori infection in Ningxia. [ABSTRACT FROM AUTHOR]
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- 2023
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6. The electric and magnetic properties of novel two-dimensional MnBr2 and MnI2 from first-principles calculations.
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Luo, Jia, Xiang, Gang, Tang, Yongliang, Ou, Kai, and Chen, Xianmei
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ELECTRIC properties ,WIDE gap semiconductors ,MAGNETIC properties ,PHONONS - Abstract
The structural, electronic, and magnetic properties of two-dimensional (2D) manganese dibromide (MnBr
2 ) and manganese diiodide (MnI2 ) are investigated using first principles calculations. The dynamical and thermal stabilities of 2D MnBr2 and MnI2 have been illustrated from the phonon dispersion and molecular dynamic calculations. From the phonon dispersion, three Raman-active and three infrared-active vibration modes are found. The calculated formation energies and cleavage energies indicate that 2D MnBr2 and MnI2 are energetically stable and could be potentially obtained by exfoliation. The hybrid functional theory is employed to discover that 2D MnBr2 and MnI2 are wide gap semiconductors. The magnetic frustration is revealed by the calculation of magnetic exchange interaction and magnetocrystalline anisotropy interaction. By analyzing different magnetic orders, the relatively weak magnetic exchange is attributed to the competition of the direct exchange and the superexchange interaction. [ABSTRACT FROM AUTHOR]- Published
- 2020
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7. Multifunctional Integrated Underwater Sound Absorption Materials: A Review.
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Chen, Xianmei, Meng, Lei, Liu, Zibo, Yang, Feiran, Jiang, Xin, and Yang, Jun
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UNDERWATER acoustics ,ABSORPTION of sound ,HYDROSTATIC pressure ,CORROSION prevention ,SUBMERSIBLES - Abstract
Rapid improvements in underwater vehicle technology have led to a significant increase in the demand for underwater sound absorption materials. These materials, unlike their counterparts utilized in air, must have high hydrostatic pressure resistance, corrosion resistance, and other advantageous attributes. This necessitates the development of innovative, composite sound-absorbing materials with multifunctional properties, which presents substantial challenges for researchers. In this comprehensive review, we systematically analyze and categorize the mechanisms governing underwater sound absorption, hydrostatic pressure resistance, and corrosion prevention while considering related research advances. Furthermore, we provide an extensive overview of research advancements, existing challenges, and potential solutions pertaining to multifunctional and integrated underwater sound-absorbing materials. This review aims to serve as a valuable resource for future investigations into the development and optimization of multifunctional integrated underwater sound-absorbing materials, thereby contributing to the advancement of underwater vehicle technology. [ABSTRACT FROM AUTHOR]
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- 2023
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8. White Photoluminescence in Dy-Doped Oxyfluoride Glasses.
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Chen, Xianmei, Khamenok, Artemiy V., Khusainov, Shaukat G., Shestakov, Mikhail V., and Moshchalkov, Victor V.
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OXYFLUORIDES ,DOPING agents (Chemistry) ,QUENCHING (Chemistry) ,WAVELENGTHS ,PHOTOLUMINESCENCE ,RARE earth metals - Abstract
Dy
3+ -doped, Ag and Dy3+ -co-doped, and Tm3+ and Dy3+ -co-doped oxyfluoride glasses have been prepared by a conventional melt-quenching method. White and yellowish light emissions were generated in the glasses under excitation in the range from 350 to 390 nm. Changes in the excitation wavelength in the ultraviolet (UV) range do not significantly alter the emission tint of the Dy and Ag and Dy-co-doped glasses. On the contrary, the tint of the Tm and Dy co-doped glasses considerably varies under excitation in the same range. [ABSTRACT FROM AUTHOR]- Published
- 2023
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9. Hydrothermal synthesis of the intense green photoluminescence of hexagonal phase NaYF4:Yb3+/Er3+ microcrystals
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Jiao, Yuechao, Gao, Xiaoyong, Lu, Jingxiao, Chen, Yongsheng, He, Wei, Chen, Xianmei, Li, Xinli, and Li, Rui
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- 2013
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10. Multi-color inkless UV printing using angle-independent structural color paper.
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Ai, Meixing, Wang, Zhihao, Chen, Xianmei, Chen, Chong, Wang, Yunlong, and Ma, Jun
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Inkless photonic paper has shown great potential as an alternative to traditional paper due to its unique structural color, which is dye-free and non-photobleaching. However, it is still highly challenging to produce large-area photonic crystal paper, and its angle dependence, complicated printing procedure, and difficulty of high-resolution printing have greatly limited its applications. To address these challenges, we developed a new UV printing strategy using amorphous structured inverse opal PEGDA photonic paper. The photonic paper is prepared using an amorphous assembly of colloidal SiO
2 particles as templates, which are fabricated by spray coating dispersions of SiO2 particles with the addition of carbon black. The photonic paper possesses structural color with low angle independency when the observation angle varies from 0° to 40°, and the unvivid structural color can be tuned in the whole visible region by exposure to UV radiation for different amounts of time, providing a fast, convenient and high-resolution printing technique. Through a chromatic-printing-like method using a series of different masks, multi-color printing is also realized. The printed images can be further protected from UV irradiation using a layer of PET film, which provides a method to store the printings for a longer time in a harsh environment. [ABSTRACT FROM AUTHOR]- Published
- 2022
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11. Aromatase excess syndrome in a Chinese boy due to a novel duplication at 15q21.2.
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Tan, Xinrui, Wu, Xiaochuan, Chen, Jie, Wu, Yan, Li, Shijun, Chen, Xianmei, and Zhang, Xingxing
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Background: Aromatase excess syndrome (AEXS) is a rare autosomal dominant disorder caused by CYP19A1 overexpression. Clinical manifestations of AEXS include pre- or peri-pubertal gynecomastia, advanced bone age and compromised adult height. Case presentation: Here we report an 8-year-old boy diagnosed with AEXS by chromosomal array that revealed a 1.1 Mb novel de novo duplication at 15q21.2, with a predicted final height of 157.4 cm. We prescribed letrozole and growth hormone (GH) to maximize his linear growth. Without further bone age advancement, his height increased from 137.7 cm to 144 cm after an 8-month treatment period. Conclusions: We identified a novel duplication at 15q21.2 in AEXS, and found that aromatase inhibitor (AI) plus GH might provide a better growth-promoting approach for AEXS patients. [ABSTRACT FROM AUTHOR]
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- 2019
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12. Prevalence of High-Risk Human Papillomavirus Infection in China: Analysis of 671,163 Human Papillomavirus Test Results From China's Largest College of American Pathologists-Certified Laboratory.
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Zeng, Zhengyu, Austin, R Marshall, He, Xuekui, Chen, Xianmei, Guo, Xiaolei, Zheng, Baowen, Wu, Shangwei, Yang, Huaitao, and Zhao, Chengquan
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PAPILLOMAVIRUS diseases ,POLYMERASE chain reaction ,DISEASE prevalence ,RETROSPECTIVE studies ,EARLY detection of cancer - Abstract
Objectives: This study on human papillomavirus (HPV) testing in China's largest independent laboratory accredited by the international Laboratory Accreditation Program of the College of American Pathologists extends previous reports on cervical screening test results from this Chinese facility.Methods: A retrospective laboratory database search from 2007 to 2014 documented high-risk HPV test results using either Hybrid Capture 2 (HC2; Qiagen, Hilden, Germany) or multiplex polymerase chain reaction fluorescence testing (MPFT) methods.Results: During the study period, HPV testing steadily increased, with 643,702 HC2 and 27,641 MPFT HPV tests performed. The mean ages of the tested women were 35.0 years using HC2 and 38.3 years using MPFT. The HC2 HPV-positive rate was 21.7%, significantly higher than 15.7% with MPFT (P < .0001), with bimodal peak incidence in adolescents and women aged 60 to 69 years.Conclusions: Use of HPV testing in cervical screening is increasing in China. HC2 HPV-positive rates around 20% in all age groups from more than 500,000 tested Chinese women are consistent with previous reports from China and significantly higher than published HC2 HPV-positive rates in populations with more widespread cervical screening. MPFT HPV-positive rates were slightly lower in every age group. The high HPV-positive rate likely reflects limited routine cervical screening and high cervical cancer incidence in China. [ABSTRACT FROM AUTHOR]- Published
- 2016
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13. Conveying characteristics and resistance characteristics in dense phase pneumatic conveying of rice husk and blendings of rice husk and coal at high pressure
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He, Chunhui, Chen, Xianmei, Wang, Jianhao, Ni, Hongliang, Xu, Yupeng, Zhou, Haijun, Xiong, Yuanquan, and Shen, Xianglin
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RICE hulls , *HIGH pressure (Technology) , *COAL , *PNEUMATIC-tube transportation , *GAS flow , *STABILITY (Mechanics) , *CHEMISTRY experiments , *STATISTICAL correlation - Abstract
Abstract: Dense phase pneumatic conveying experiment of rice husk powder and blendings of rice husk and coal was carried out at the pressure of up to 4.0MPa in an experimental facility. Effects of operation conditions and mixing ratios of rice husk and coal on conveying behaviours were investigated. Results indicated that superficial gas velocity increased as total conveying differential pressure and supplemental gas flow rate increased, respectively. Solid loading ratio increased with increasing total conveying differential pressure, but decreased with increasing supplemental gas flow rate. Under the same operation conditions, superficial gas velocity decreased with the increasing in content of coal in blendings, while solid loading ratio increased gradually. The flow stability analysis results indicated that conveyings of blendings were more stable than that of pure rice husk, the flow stability was improved by adding coal. Characteristics of pressure drops in horizontal pipe, vertical pipe, horizontal bend and vertical bend were presented. Empirical correlations of additional pressure drop coefficients and pressure drops of vertical pipe, horizontal pipe, vertical bend and horizontal bend were proposed. [Copyright &y& Elsevier]
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- 2012
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14. Direct Observation of Nanoscale Light Confinement without Metal.
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Liu, Yunxin, Vanacken, Johan, Chen, Xianmei, Han, Junbo, Zhong, Zhiqiang, Xia, Zhengcai, Chen, Borong, Wu, Huan, Jin, Zhao, Ge, Jun‐Yi, Huang, Junwei, Meng, Lei, Duan, Xiangfeng, Huang, Yu, Peng, Qing, Moshchalkov, Victor V., and Li, Yadong
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- 2019
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15. Hydrothermal synthesis of the intense green photoluminescence of hexagonal phase NaYF4:Yb3+/Er3+ microcrystals
- Author
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Jiao, Yuechao, Gao, Xiaoyong, Lu, Jingxiao, Chen, Yongsheng, He, Wei, Chen, Xianmei, Li, Xinli, and Li, Rui
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PHOTOLUMINESCENCE , *PHASE transitions , *EUROPIUM compounds , *METAL ions , *INORGANIC synthesis , *METAL crystals , *ETHYLENEDIAMINETETRAACETIC acid , *CRYSTAL structure - Abstract
Abstract: Hexagonal phase NaYF4:Yb3+ 20mol%/Er3+ 1mol% microcrystals that exhibit intense green emission were successfully synthesized via a facile hydrothermal method. The factors including the NaF/Ln (Ln=Y+Yb+Er) molar ratio, pH value of the precursor solution, and the ethylenediaminetetraacetic acid (EDTA)/Ln molar ratio, were well studied in the influences on the crystal structures, morphologies, and sizes of final products. The experimental results indicate that the NaF/Ln ratio and pH value play key roles in crystal structure and morphology of the product. Photoluminescence measurements demonstrate that the relative up-conversion photoluminescence intensity of as-prepared products strongly depends on the crystal structures, crystallization degrees, morphologies, and sizes. [Copyright &y& Elsevier]
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- 2013
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16. Effect of statins on pulmonary function in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis of randomized controlled trials.
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Chen X, Hu F, Chai F, and Chen X
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Background: Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease, and its treatment is still controversial. Statins have been proven to have anti-inflammatory and immunomodulatory effects, but their effectiveness in the treatment of COPD is still unclear. We conducted this meta-analysis to more accurately evaluate the therapeutic effect of statins on COPD patients., Methods: Randomized controlled studies published in PubMed, Cochrane Library, Embase, Wiley Online Library, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases from inception to July 2022 were retrieved to evaluate the effect of statins on COPD patients. Two evaluators conducted literature screening based on inclusion and exclusion criteria, and conducted a bias risk assessment on them. Meta analysis was conducted using Stata17.0 statistical software., Results: A total of 1,463 patients from 10 studies were included. After statin treatment, the percentage of predicted forced expiratory volume in the first second (FEV1%pred) of COPD patients was improved [weighted mean difference (WMD): 7.89; 95% confidence interval (CI): 7.19-8.60; P<0.05], and the level of the inflammatory factor C-reactive protein (CRP) decreased (WMD: -0.63; 95% CI: -1.84, 0.58; P<0.05). The 6-minute walking distance (6MWD) of patients in the statin treatment group demonstrated a significant benefit (WMD: 26.27; 95% CI: 24.02-28.51; P<0.05). Compared to the placebo control group, statins significantly reduced COPD Assessment Test (CAT) (WMD: -2.45; 95% CI: -3.62, -1.27)., Conclusions: Preliminary evidence suggests that statins may have a certain effect on improving lung function, reducing inflammatory factor levels, and improving clinical symptoms in COPD patients. However, due to the quality and quantity limitations of the included studies, these results need to be further verified through a larger, higher quality randomized controlled trial (RCT)., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1042/coif). The authors have no conflicts of interest to declare., (2023 Journal of Thoracic Disease. All rights reserved.)
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- 2023
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17. Prevalence and risk factors of Helicobacter pylori infection in Ningxia, China: comparison of two cross-sectional studies from 2017 and 2022.
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Zhou Y, Deng Y, You Y, Li X, Zhang D, Qi H, Shi R, Yao L, Tang Y, Li X, Ma L, Li Y, Liu J, Feng Y, Chen X, Hao Q, Li X, Li Y, Niu M, Gao H, Bai F, and Hu S
- Abstract
Objectives: Helicobacter pylori ( H. pylori ) infection causes a variety of intragastric and extragastric diseases. Despite its decreasing global prevalence, it remains a major public health problem in many developing countries. This study aimed to understand the prevalence of H. pylori infection and its risk factors in five cities of the Ningxia Hui Autonomous Region, an area with high incidence of gastric cancer., Methods: Cross-sectional studies were conducted in Ningxia from 2017 and 2022, to detect the prevalence of H. pylori using the
14 C urea breath test. All participants completed a questionnaire that included demographics, personal habits, household economic characteristics, and previous health status. Multiple logistic regression analyses were used to identify independent factors for H. pylori infection., Results: Our findings demonstrated that the prevalence of H. pylori infection in Ningxia decreased significantly from 60.3% in 2017 to 43.6% in 2022, with an increase in public awareness rate from 35.9% in 2017 to 68.5% in 2022. The lowest infection rate was found in Zhongwei and highest in Guyuan. The prevalence of H. pylori infection was higher among Hui ethnicity, farmers, individuals living in rural areas, individuals with lower income, low education, and those who consumed less fruit. Gallbladder, respiratory, cardiovascular and autoimmune diseases were not associated with H. pylori infection., Conclusions: The prevalence of H. pylori in Ningxia decreased in the past five years. Ethnicity, location, occupation, income, education, and consumption of fruits were independent risk factors for H. pylori infection in Ningxia. It was not associated with extra-gastric disease., Competing Interests: None., (AJTR Copyright © 2022.)- Published
- 2022
18. A Survey of Helicobacter pylori Antibiotic-Resistant Genotypes and Strain Lineages by Whole-Genome Sequencing in China.
- Author
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Zhou Y, Zhong Z, Hu S, Wang J, Deng Y, Li X, Chen X, Li X, Tang Y, Li X, Hao Q, Liu J, Sang T, Bo Y, and Bai F
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- Amoxicillin therapeutic use, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Clarithromycin pharmacology, Clarithromycin therapeutic use, Drug Resistance, Bacterial genetics, Genotype, Humans, Levofloxacin pharmacology, Levofloxacin therapeutic use, Metronidazole therapeutic use, Microbial Sensitivity Tests, Helicobacter Infections drug therapy, Helicobacter pylori
- Abstract
Antibiotic resistance is the most important factor leading to failed Helicobacter pylori eradication therapy, and personalized treatment based on antibiotic susceptibility is becoming increasingly important. To strengthen the understanding of antibiotic genotypic resistance of H. pylori and identify new antibiotic resistance loci, in this study, we identified phenotypic resistance information for 60 clinical isolates and compared the concordance of phenotypic and genotypic resistance using whole-genome sequencing (WGS). Clarithromycin and levofloxacin genotypic resistance was in almost perfect concordance with phenotypic resistance, with kappa coefficients of 0.867 and 0.833, respectively. All strains with the R16H/C mutation and truncation in rdxA were metronidazole resistant, with 100% specificity. For other genes of concern, at least one phenotypically sensitive strain had a previous mutation related to antibiotic resistance. Moreover, we found that the A1378G mutation of HP0399 and the A149G mutation of FabH might contribute to tetracycline resistance and multidrug resistance, respectively. Overall, the inference of resistance to clarithromycin and levofloxacin from genotypic resistance is reliable, and WGS has been very helpful in discovering novel H. pylori resistance loci. In addition, WGS has also enhanced our study of strain lineages, providing new ways to understand resistance information and mechanisms.
- Published
- 2022
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