29 results on '"Ruisheng Yang"'
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2. Biology of Rhynchaenus maculosus provides insights and implications for integrated management of this emerging pest
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Ruisheng Yang, Pengcheng Qiu, Yujian Gu, Mingyang Ni, Zhenhai Xue, Jianhua Han, Yiren Jiang, Ying Jin, Yong Wang, Xinfeng Zhou, Wei Liu, Jihui Zhang, and Li Qin
- Subjects
Medicine ,Science - Abstract
Abstract Rhynchaenus maculosus is an emerging insect pest with an increasingly serious tendency. Lack of biology information results in the bottleneck of integrated management of this pest. To facilitate an available design of integrated pest management strategy, biology of R. maculosus, including voltinism, life cycle, distribution, and damage has been investigated. Results reveal that R. maculosus is oligophagous and distributes in Heilongjiang, Jilin, and Liaoning provinces, China. This pest produces one generation per year (univoltinism) and overwinters as adults in leaf litter. From mid-April to late-April, active overwintering adults emerge from overwintering sites. The next generation of adult R. maculosus appears from mid-May to early June until mid-August to early September when the beetles move into the overwintering places. The entire time span of adult occurrence ranges from 315.6 ± 3.6 to 336.4 ± 3.2 days (Mean ± SD). Larvae undergo 3 instars with a total duration of 20 to 23 days. R. maculosus larvae feed on Q. wutaishanica and Q. mongolica without host-specific preference between the two host species, but do not harm Q. acutissim. Three species of larval parasites were collected and identified as Braconidae sp., Eulophidae sp., and Ceraphronidae sp. Biological information of R. maculosus provides essential insights for design and implementation of integrated management of this pest.
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- 2022
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3. Coupling Controlled Dual‐Band Tunable Electromagnetic Extraordinary Transmission in Graphene Hybrid Metasurfaces
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Jiameng Nan, Yujing Zhang, Yu Xie, Zhichen Li, Ruisheng Yang, Jing Xu, Quanhong Fu, Fuli Zhang, and Yuancheng Fan
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EM waves ,extraordinary transmission ,graphene ,hybrid metasurfaces ,tunability ,Electric apparatus and materials. Electric circuits. Electric networks ,TK452-454.4 ,Physics ,QC1-999 - Abstract
Abstract A metasurface is a kind of ultrathin artificial composite composed of subwavelength elements with unique abilities in manipulating electromagnetic waves. However, the static nature of its conventional metallic/dielectric constituent material has limited its fixed functionality in narrow frequency ranges. The two‐dimensional carbon sheet, i.e., graphene, is a promising platform for effectively tuning the functionality as well as operation frequency band of metasurface. Here, the authors propose and demonstrate a kind of graphene hybrid metasurface for dual‐band extraordinary electromagnetic transmission (EET). The metasurface is composed of two graphene/metal hybrid resonators with EET properties. It is shown that the EET of the graphene hybrid metasurfaces can be tuned by increasing the bias voltage on the graphene from 0 to 3 V. Furthermore, it is found that the transmission amplitude and operating frequency band of EET can be controlled by changing the relative position and thus the coupling of the two graphene hybrid resonators. The proposed design strategy of the hybrid metasurfaces is promising for many applications based on active EM or optical modulations.
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- 2023
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4. Coupled magnetic Mie resonances induced extraordinary optical transmission and its non-linear tunability
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Weiqi Cai, Lixin Xuan, Yuancheng Fan, Ruisheng Yang, Wenwu Zhang, Qing Zhang, Songnan Chen, Zhehao Ye, Yujing Zhang, Quanhong Fu, and Fuli Zhang
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extraordinary optical transmission ,non-linear ,tunable metamaterials ,Mie resonance ,dielectric metamaterials ,Technology - Abstract
Dielectric metamaterials with low ohmic losses and resonating in the local magnetic mode are preferable for enhancing material non-linearity. Here, we propose and experimentally demonstrate broadband extraordinary electromagnetic transmission (EET) behavior, which is induced by the coupling of magnetic modes of two ceramic cuboids. It is shown that extraordinary electromagnetic transmission behavior through a perforated metal sheet with a subwavelength aperture can be achieved by exciting the first-order magnetic mode Mie resonant coupling of these cuboids. Our findings indicate that the transmission bandwidth and amplitude are dependent on the strength of coupling between the two ceramic cuboids. Additionally, we utilized non-linear effects within the dielectric cuboids to achieve tunable extraordinary electromagnetic transmission behavior. Our results are promising for developing non-linearly tunable microwave devices such as filters and modulators of their strong light-matter interactions.
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- 2023
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5. The Birefringence and Extinction Coefficient of Ferroelectric Liquid Crystals in the Terahertz Range
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Ying Ma, Yuhang Shan, Yongning Cheng, Ruisheng Yang, Hoi-Sing Kwok, and Jianlin Zhao
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liquid crystal ,birefringence ,extinction ,terahertz ,Applied optics. Photonics ,TA1501-1820 - Abstract
In this paper, the refractive index and extinction coefficient of ferroelectric liquid crystals have been examined by the terahertz time-domain spectroscopy system. Two modes of ferroelectric liquid crystal materials, deformed helix ferroelectric liquid crystal (DHFLC), and electric suppressed helix ferroelectric liquid crystal (ESHFLC) are tested as experimental samples. Nematic liquid crystal (NLC) was also investigated for comparison. The birefringence of DHFLC 587 slowly increases with the growth of frequency, and it averages at 0.115. Its extinction coefficients gradually incline to their stable states at 0.06 for o-wave and 0.04 for e-wave. The birefringence of ESHFLC FD4004N remains between around 0.165 and 0.175, and both of its e-wave and o-wave extinction coefficients are under 0.1, ranging from 0.05 to 0.09. These results of FLC will facilitate the examination and improve the response performance of THz devices using fast liquid crystal materials.
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- 2023
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6. Experimental study on complex stress effect for stress relaxation aging behavior of Al-Cu-Li alloy
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Hailong Liao, Lihua Zhan, Feng Xia, Minghui Huang, Chunhui Liu, Shengmeng Hui, Peng Wang, Ruisheng Yang, and Xiaobo Wang
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Stress relaxation aging ,The initial stress level ,Al-Cu-Li ,Double stage relaxation behavior ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The highlight of this work is to investigate the effect of complex initial stress levels (from elastic to plastic regions) on the Stress relaxation aging (SRA) behavior of T34-2195 Al-Cu-Li alloys. The uniaxial tensile SRA experiment with various initial stress levels was carried out at 180 °C for 16 h. A novel double stage relaxation behavior is observed and analyzed theoretically by X-ray diffraction peak-broadening (XRD) and transmission electron microscopy (TEM). When initial stress levels (the plastic region) are higher than the yield strength at 180 °C, the stress relaxation curves show the traditional single stage relaxation behavior. When initial stress levels (the elastic region) are lower than the yield strength, stress relaxation curves display four stages where a novel double stage relaxation behavior was observed, and four stages comprise the following parts: (1) the initial variable-rate and steady-rate relaxation stages; (2) the second variable-rate and second steady-state relaxation stages. The results show that a double stage relaxation behavior was scribed to the interaction among the dislocation, solute atoms and T1 (Al2CuLi) phase. The main reason for the difference between elastic and plastic initial stresses is the different dislocation density caused by the various initial stresses.
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- 2022
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7. A novel dual-prodrug carried by cyclodextrin inclusion complex for the targeting treatment of colon cancer
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Lin Chen, Yan Lin, Zijun Zhang, Ruisheng Yang, Xiaosheng Bai, Zhongbing Liu, Zhongling Luo, Meiling Zhou, and Zhirong Zhong
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Butyric acid ,5-Aminosalicylic acid ,Prodrug ,Inclusion complex ,Colon cancer ,Biotechnology ,TP248.13-248.65 ,Medical technology ,R855-855.5 - Abstract
Abstract Background There is an obvious correlation between ulcerative colitis and colorectal cancer, and the risk of colorectal cancer in patients with ulcerative colitis is increasing. Therefore, the combination therapy of anti-inflammatory and anti-tumor drugs may show promising to inhibit colon cancer. 5-aminosalicylic acid (5-ASA) with anti-inflammatory function is effective for maintaining remission in patients with ulcerative colitis and may also reduce colorectal cancer risk. Histone deacetylase (HDAC) plays an essential role in the progression of colon cancer. Butyric acid (BA) is a kind of HDAC inhibitor and thus shows tumor suppression to colon cancer. However, the volatile and corrosive nature of BA presents challenges in practical application. In addition, its clinical application is limited due to its non-targeting ability and low bioavailability. We aimed to synthesize a novel dual-prodrug of 5-ASA and BA, referred as BBA, to synergistically inhibit colon cancer. Further, based on the fact that folate receptor (FR) is over-expressed in most solid tumors and it has been identified to be a cancer stem cell surface marker in colon cancer, we took folate as the targeting ligand and used carboxymethyl-β-cyclodextrin (CM-β-CD) to carry BBA and thus prepared a novel inclusion complex of BBA/FA-PEG-CM-β-CD. Results It was found that BBA/FA-PEG-CM-β-CD showed significant inhibition in cell proliferation against colon cancer cells SW620. It showed a pro-longed in vivo circulation and mainly accumulated in tumor tissue. More importantly, BBA/FA-PEG-CM-β-CD gave great tumor suppression effect against nude mice bearing SW620 xenografts. Conclusions Therefore, BBA/FA-PEG-CM-β-CD may have clinical potential in colon cancer therapy. Graphical Abstract
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- 2021
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8. Subwavelength optical localization with toroidal excitations in plasmonic and Mie metamaterials
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Ruisheng Yang, Jing Xu, Nian‐Hai Shen, Fuli Zhang, Quanhong Fu, Junjie Li, Hongqiang Li, and Yuancheng Fan
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dielectric metamaterials ,metamaterials ,subwavelength optics ,toroidal metasurfaces ,toroidal moment ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Information technology ,T58.5-58.64 - Abstract
Abstract Since the performance of electronic circuits is becoming rather limited in face of intensively increasing of amount of information and related operations, all‐optical processing offers a promising strategy for future information system. It would benefit a great deal if the all‐optical processing could be implemented within the developed electronic chips of nanoscale structures. In that it is highly desirable to break the diffraction limit of light for achieving effective light manipulations with deep subwavelength structures compatible with the state‐of‐the‐art nanofabrication processes. It is of fundamental importance to get subwavelength optical localization, that is, squeeze light wave into subwavelength space for achieving freely manipulating of light fields. This review summarizes the development in realizing subwavelength optical localization by exciting toroidal mode in photonic metamaterials. The toroidal excitations in plasmonic metamaterials and Mie resonant metamaterials, in 3D structures and planar metamaterials, with single or few layers in spectral regime from microwave to optical frequencies are surveyed. Based on the discussion on the configurations of toroidal excitations, the recent development on toroidal‐related optical scattering control actively manipulates the toroidal excitations, and promising applications are further investigated and highlighted.
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- 2021
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9. Tyrosine Hydroxylase and DOPA Decarboxylase Are Associated With Pupal Melanization During Larval–Pupal Transformation in Antheraea pernyi
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Qi Wang, Liang Zhong, Yong Wang, Shengwei Zheng, Yumeng Bian, Junhao Du, Ruisheng Yang, Wei Liu, and Li Qin
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Antheraea pernyi ,pupal melanization ,tyrosine hydroxylase ,DOPA decarboxylase ,RNA interference ,enzyme inhibitor ,Physiology ,QP1-981 - Abstract
In insects, melanism plays important roles in defense, immunoreactions, and body color. The underlying molecular mechanisms of melanism in different insects are diverse and remain elusive. In contrast to another silkworm, Bombyx mori, the Chinese oak silkworm, Antheraea pernyi, produces melanic pupae under natural environmental conditions. DOPA and dopamine synthesis are crucial for melanin formation. Disruption of these processes reportedly influences body colors in many insects. Most research focuses on newly emerged pupae, and the larval process preceding pupation remains unknown. Due to the large size and long pupation period in A. pernyi, the entire process was studied at least every 12 h. The expression patterns of tyrosine hydroxylase (TH) and DOPA decarboxylase (DDC), which are involved in DOPA and dopamine synthesis in the epidermis, were evaluated during larval–pupal metamorphosis. We also performed RNA interference (RNAi) and used enzyme inhibitors to examine morphological changes. The amino acid sequences of TH and DDC share 90.91% and 86.64% identity with those of B. mori. TH and DDC expression was upregulated during the 48–72 h period prior to pupal emergence, especially at 60 h. RNAi of TH and DDC induced partial melanism in some pupae. The inhibitors 3-iodo-tyrosine (3-IT) and L-α-methyl-DOPA (L-DOPA) influenced pupal melanization. Different concentrations of inhibitors led to pupal deformity and even mortality. Four different monoamines, only DOPA and Dopamine synthezed from Tyrosine will be influenced by TH and DDC inhibitor. These results indicate that TH and DDC are key genes associated with pupal melanization during larval–pupal transformation in A. pernyi. Overall, our results suggest that TH and DDC expression alterations in a particular stage can affect body color, setting the molecular basis for artificial control of pupal melanization.
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- 2022
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10. Active Control of Terahertz Toroidal Excitations in a Hybrid Metasurface with an Electrically Biased Silicon Layer
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Ruisheng Yang, Jing Lou, Fuli Zhang, Wei Zhu, Jing Xu, Tong Cai, Quanhong Fu, Hongqiang Li, and Yuancheng Fan
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high Q ,phase-change metasurfaces ,toroidal excitations ,tunable metasurfaces ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
The active control of artificially structured metasurfaces is a promising route for solving the operation bandwidth limitation of metasurfaces due to their resonant nature. Herein, the active tunability of the toroidal response in a terahertz hybrid metasurface is proposed and experimentally demonstrated. The top metallic layer of the metasurface has a toroidal configuration and is coupled to an electrically biased phase‐change silicon layer, whose conductive thickness and conductivity can be changed significantly when applying increased external current. The electrically biased hybrid metasurface shows high efficiency and complete electrical switching on the toroidal response in a broadband manner. Also, the optoelectronic metasurfaces modulated by biased currents are much easier to integrate in on‐chip optical devices. The hybrid metasurface taking advantage of the silicon layer with insulating‐state to conductive‐state transition in optical conductivity may facilitate the development of high‐performance active photonic applications in, for example, smart sensing in the terahertz regime.
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- 2021
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11. Actively Controlled Frequency-Agile Fano-Resonant Metasurface for Broadband and Unity Modulation
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Ruisheng Yang, Quanhong Fu, Yuancheng Fan, Jing Xu, Wei Zhu, Weiqi Cai, and Fuli Zhang
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frequency-agile metasurfaces ,fano resonance ,varactor diodes ,temporal coupled-mode theory ,modulator ,Physics ,QC1-999 - Abstract
The active control to the local resonant mode of metasurface is a promising route for improving the operation bandwidth limitation of metasurface. Here, we propose and experimentally demonstrated the active tunabilities in a frequency-agile Fano-resonant metasurface. The metasurface with a pair of asymmetric split ring resonators is integrated with double varactor diodes for active control of the sharp Fano resonance. It is found that the sharp Fano-type spectrum appears due to the near-field interferences between the collective electric and magnetic dipole modes. The physical insight is revealed through local field analysis, multipole decomposition and temporal coupled-mode theory. It is also found that the metasurface can be employed as a broadband and unity modulator. Hopefully, our results could inspire sophisticated electrically controlled photonic devices with novel functions.
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- 2021
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12. Dual‐Sensitivity Terahertz Metasensor Based on Lattice–Toroidal‐Coupled Resonance
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Jing Lou, Ruisheng Yang, Jiangang Liang, Ying Yu, Lei Zhang, Chiben Zhang, Tangjing Li, Yuancheng Fan, Fuli Zhang, Guangming Wang, Jun Wang, and Tong Cai
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dual-sensitivities ,metamaterials ,mode coupling ,terahertz sensing ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
High quality factor resonance with extremely narrow line‐width offers an important platform for terahertz (THz) sensing technology as it enables strong light‐matter interaction between THz waves and analyte materials. Lattice mode arising from the collective Rayleigh scattering of metamaterial periodic structures has the ability to strongly confine the electromagnetic waves on the surface that fails to radiate to the far‐field. Herein, for the first time, a strategy is experimentally demonstrated to design THz metasensors, which exhibit dual‐sensitivity of frequency and resonance intensity by coupling the first‐order lattice mode to the toroidal resonance. The frequency sensitivity mainly results from the localized field confinement, whereas the sensitivity of resonance intensity depends on the matching degree between toroidal resonance and lattice mode. It is found that both the frequency shift and resonance intensity show exponential growth with the increase in the analyte thickness. In addition, the sensing performance between toroidal and toroidal–lattice modes is compared to verify the superiority of the dual‐sensitivity property. This work would greatly improve the practical applications of THz sensing technology and open up new opportunities for the realization of slow light devices, multiband narrow filters, and nonlinear systems.
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- 2021
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13. A Review of Tunable Electromagnetic Metamaterials With Anisotropic Liquid Crystals
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Jing Xu, Ruisheng Yang, Yuancheng Fan, Quanhong Fu, and Fuli Zhang
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tunable metamaterials ,negative index metamaterial ,liquid crystals ,Liquid crystals reorientations ,reconfigurable metamaterials ,Physics ,QC1-999 - Abstract
The performance of metamaterial is limited to a designed narrow band due to its resonant nature, it is highly desirable to incorporate active inclusions in metamaterials to extend the operation bandwidth. This review summarizes the development in realizing the tunability of electromagnetic response in metamaterials incorporated with nematic liquid crystal (LC). From rigorous comparison, it is found that the anisotropic property of nematic LC is essential in predicting the influence of LC molecular director orientation on the resonant frequency of metamaterials. By carefully designing the metamaterials and properly infiltrating LC, the operation frequency of single/double negative parameters of metamaterials can be dynamically modulated with remarkable red/blue-shift, depending on the LC molecular orientation angle. Moreover, the recent liquid crystal-based developments and novel applications are investigated and highlighted.
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- 2021
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14. The first report of fully sequenced resistance plasmid from Shigella boydii
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Li Wang, Lei Liu, Dong Liu, Zhe Yin, Jiao Feng, Defu Zhang, Fang Hai Hong, Yefeng Qiu, Weijun Chen, Ruisheng Yang, Jinglin Wang, Yunzhi Fa, and Dongsheng Zhou
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Shigella boydii ,erm(B) ,p2246-CTXM ,blaCTX-M-14 ,mph(A) ,Microbiology ,QR1-502 - Abstract
The purpose of this study was to characterize mechanisms of plasmid-mediated antimicrobial resistance in Shigella boydii. S. boydii strain 2246 with resistance to ciprofloxacin, ceftriaxone and azithromycin was isolated from a human case of watery diarrhea in a Chinese public hospital. Resistance in strain 2246 to ceftriaxone and azithromycin was attributable to the presence of blaCTX-M-14, and erm(B) and mph(A), respectively, which were co-located on a multidrug-resistant (MDR) plasmid p2246-CTXM. p2246-CTXM represented a novel IncFII-type MDR plasmid with a very complex chimera structure. Its master backbone was genetically closely related to the R100 plasmid, but p2246-CTXM had evolved to integrate additional R100-unrelated backbone regions as well as massive exogenous mobile elements that carried multiple resistance determinants. In p2246-CTXM, erm(B) together with its leading peptide gene erm(C), mph(A) together with its regulatory genes mrx and mphR(A), and blaCTX-M-14 were captured by three different mobile elements Tn6295, the IS26-mph(A)-mrx-mphR(A)-IS6100 unit, and a truncated ISEcp1-blaCTX-M-14-IS903D-iroN transposition unit, respectively, all of which were harbored in a large Tn3-family transposon Tn6285. p2246-CTXM still carried additional resistance determinants mer (mercury resistance), aacA4 (aminoglycoside resistance), cmlA1 (chloramphenicol resistance) and qacED1 (quaternary ammonium compound resistance). This is the first report of identifying a clinical S. boydii strain simultaneously resistant to ciprofloxacin, ceftriaxone and azithromycin, and determining the complete sequence of a resistance plasmid from S. boydii.
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- 2016
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15. The Toll Signaling Pathway in the Chinese Oak Silkworm, Antheraea pernyi: Innate Immune Responses to Different Microorganisms.
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Ying Sun, Yiren Jiang, Yong Wang, Xisheng Li, Ruisheng Yang, Zhiguo Yu, and Li Qin
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Medicine ,Science - Abstract
The Toll pathway is one of the most important signaling pathways regulating insect innate immunity. Spatzle is a key protein that functions as a Toll receptor ligand to trigger Toll-dependent expression of immunity-related genes. In this study, a novel spatzle gene (ApSPZ) from the Chinese oak silkworm Antheraea pernyi was identified. The ApSPZ cDNA is 1065 nucleotides with an open reading frame (ORF) of 777 bp encoding a protein of 258 amino acids. The protein has an estimated molecular weight of 29.71 kDa and an isoelectric point (PI) of 8.53. ApSPZ is a nuclear and secretory protein with no conserved domains or membrane helices and shares 40% amino acid identity with SPZ from Manduca sexta. Phylogenetic analysis indicated that ApSPZ might be a new member of the Spatzle type 1 family, which belongs to the Spatzle superfamily. The expression patterns of several genes involved in the Toll pathway were examined at different developmental stages and various tissues in 5th instar larvae. The examined targets included A. pernyi spatzle, GNBP, MyD88, Tolloid, cactus and dorsalA. The RT-PCR results showed that these genes were predominantly expressed in immune-responsive fat body tissue, indicating that the genes play a crucial role in A. pernyi innate immunity. Moreover, A. pernyi infection with the fungus Nosema pernyi and the gram-positive bacterium Enterococcus pernyi, but not the gram-negative bacterium Escherichia coli, activated the Toll signaling pathway. These results represent the first study of the Toll pathway in A. pernyi, which provides insight into the A. pernyi innate immune system.
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- 2016
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16. The Neuropilin-1 Inhibitor, ATWLPPR Peptide, Prevents Experimental Diabetes-Induced Retinal Injury by Preserving Vascular Integrity and Decreasing Oxidative Stress.
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Jun Wang, Shuaiwei Wang, Mengling Li, Dongdong Wu, Fang Liu, Ruisheng Yang, Shaoping Ji, Ailing Ji, and Yanzhang Li
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Medicine ,Science - Abstract
Neuropilin-1 (NRP-1) is a transmembrane glycoprotein. As a VEGF co-receptor, NRP1 significantly enhances VEGFR2 signaling and promotes vascular permeability and migration. The purpose of this study was to evaluate the effects of an NRP-1 inhibitor, ATWLPPR peptide, on the early stages of diabetic retinopathy. Eight-week-old male C57BL/6 mice were divided into three groups: a Normal group, a Diabetes (DB) ATWLPPR treatment group and a DB saline group. Electroretinography (ERG), fundus fluorescence angiography (FFA) and leukostasis were examined to evaluate the retinal injury induced by diabetes at the end of the fifth week after STZ injection. Occludin expression and extravasation of albumin were measured to determine the extent of vascular injury. The oxidative stress level and the levels of inflammation-associated proteins were also assayed. The results indicated that treatment with ATWLPPR prevents the abnormal condition of ERG (amplitudes of b-wave decreased and implicit time increased) and vascular injury (occludin degradation and increase in extravasated albumin). These effects were associated with a reduction in the oxidase stress level and the expression of VEGF, GFAP, and ICAM-1. We conclude that ATWLPPR, an NRP-1 inhibitor, may reduce the early retinal damage induced by diabetes by preserving vascular integrity and decreasing the oxidative stress level. Blockade of NRP-1 may be a new therapeutic strategy for the early stages of DR.
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- 2015
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17. Actively Controlled Frequency-Agile Fano-Resonant Metasurface for Broadband and Unity Modulation
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Fuli Zhang, Jing Xu, Wei Zhu, Quanhong Fu, Ruisheng Yang, Yuancheng Fan, and Weiqi Cai
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Physics ,business.industry ,Materials Science (miscellaneous) ,QC1-999 ,varactor diodes ,Biophysics ,General Physics and Astronomy ,Fano resonance ,Physics::Optics ,modulator ,frequency-agile metasurfaces ,Split-ring resonator ,Modulation ,Broadband ,fano resonance ,Optoelectronics ,temporal coupled-mode theory ,Physical and Theoretical Chemistry ,Photonics ,business ,Magnetic dipole ,Varicap ,Local field ,Mathematical Physics - Abstract
The active control to the local resonant mode of metasurface is a promising route for improving the operation bandwidth limitation of metasurface. Here, we propose and experimentally demonstrated the active tunabilities in a frequency-agile Fano-resonant metasurface. The metasurface with a pair of asymmetric split ring resonators is integrated with double varactor diodes for active control of the sharp Fano resonance. It is found that the sharp Fano-type spectrum appears due to the near-field interferences between the collective electric and magnetic dipole modes. The physical insight is revealed through local field analysis, multipole decomposition and temporal coupled-mode theory. It is also found that the metasurface can be employed as a broadband and unity modulator. Hopefully, our results could inspire sophisticated electrically controlled photonic devices with novel functions.
- Published
- 2021
18. Dual‐Sensitivity Terahertz Metasensor Based on Lattice–Toroidal‐Coupled Resonance
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Tong Cai, Guang-Ming Wang, Ying Yu, Chiben Zhang, Ruisheng Yang, Tangjing Li, Jun Wang, Lei Zhang, Yuancheng Fan, Jing Lou, Fuli Zhang, and Jiangang Liang
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Physics ,Toroid ,Terahertz radiation ,Resonance ,Metamaterial ,mode coupling ,General Medicine ,QC350-467 ,Optics. Light ,Molecular physics ,Dual (category theory) ,TA1501-1820 ,Lattice (module) ,metamaterials ,terahertz sensing ,Mode coupling ,dual-sensitivities ,Applied optics. Photonics ,Sensitivity (control systems) - Abstract
High quality factor resonance with extremely narrow line‐width offers an important platform for terahertz (THz) sensing technology as it enables strong light‐matter interaction between THz waves and analyte materials. Lattice mode arising from the collective Rayleigh scattering of metamaterial periodic structures has the ability to strongly confine the electromagnetic waves on the surface that fails to radiate to the far‐field. Herein, for the first time, a strategy is experimentally demonstrated to design THz metasensors, which exhibit dual‐sensitivity of frequency and resonance intensity by coupling the first‐order lattice mode to the toroidal resonance. The frequency sensitivity mainly results from the localized field confinement, whereas the sensitivity of resonance intensity depends on the matching degree between toroidal resonance and lattice mode. It is found that both the frequency shift and resonance intensity show exponential growth with the increase in the analyte thickness. In addition, the sensing performance between toroidal and toroidal–lattice modes is compared to verify the superiority of the dual‐sensitivity property. This work would greatly improve the practical applications of THz sensing technology and open up new opportunities for the realization of slow light devices, multiband narrow filters, and nonlinear systems.
- Published
- 2021
19. Calibration-free, high-precision, and robust terahertz ultrafast metasurfaces for monitoring gastric cancers.
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Jing Lou, Yanan Jiao, Ruisheng Yang, Yindong Huang, Xing Xu, Lei Zhang, Zhaofu Ma, Ying Yu, Wenyu Peng, Yifang Yuan, Yuan Zhong, Songyan Li, Yang Yan, Fuli Zhang, Jiangang Liang, Xiaohui Du, Chao Chang, and Cheng-Wei Qiu
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STOMACH cancer ,MEASUREMENT errors ,OPTICAL sensors ,MEDICAL equipment ,MEDICAL innovations - Abstract
Optical sensors, with great potential to convert invisible bioanalytical response into readable information, have been envisioned as a powerful platform for biological analysis and early diagnosis of diseases. However, the current extraction of sensing data is basically processed via a series of complicated and time-consuming calibrations between samples and reference, which inevitably introduce extra measurement errors and potentially annihilate small intrinsic responses. Here, we have proposed and experimentally demonstrated a calibration-free sensor for achieving high-precision biosensing detection, based on an optically controlled terahertz (THz) ultrafast metasurface. Photoexcitation of the silicon bridge enables the resonant frequency shifting from 1.385 to 0.825 THz and reaches the maximal phase variation up to 50° at 1.11 THz. The typical environmental measurement errors are completely eliminated in theory by normalizing the Fourier-transformed transmission spectra between ultrashort time delays of 37 ps, resulting in an extremely robust sensing device for monitoring the cancerous process of gastric cells. We believe that our calibration-free sensors with high precision and robust advantages can extend their implementation to study ultrafast biological dynamics and may inspire considerable innovations in the field of medical devices with nondestructive detection. [ABSTRACT FROM AUTHOR]
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- 2022
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20. Actively modulated propagation of electromagnetic wave in hybrid metasurfaces containing graphene
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Ruisheng Yang, Fuli Zhang, Yuancheng Fan, Jing Xu, Jiameng Nan, and Quanhong Fu
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Materials science ,02 engineering and technology ,01 natural sciences ,Electromagnetic radiation ,law.invention ,Amplitude modulation ,symbols.namesake ,graphene metasurface ,extraordinary transmission ,law ,0103 physical sciences ,General Materials Science ,010306 general physics ,Sheet resistance ,business.industry ,Graphene ,Fermi level ,Biasing ,modulator ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,lcsh:QC1-999 ,Transmission (telecommunications) ,Mechanics of Materials ,Modulation ,symbols ,Optoelectronics ,conductivity ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,0210 nano-technology ,business ,lcsh:TK1-9971 ,lcsh:Physics - Abstract
Here we present the actively modulated transportation of electromagnetic wave through hybrid metasurfaces containing graphene. The hybrid metasurfaces are composed of patterned metallic layers of extraordinary transmission and backed with graphene-sandwich layers. With the designed metallic layer with perforated structure, we demonstrated effective modulation on the on-resonance transmission amplitude by increasing the bias voltage from 0 to 4 V to electrically tune the Fermi level as well as the sheet resistance of the graphene-sandwich structure. We also found that the modulation depth can be further improved by properly designing the perforated metallic structure. By change the geometry from cut-wire structure to the “butterfly”-like pattern we preliminarily achieved 19.2% improvement on the on-resonance transmission modulation. The measured transmittances of the active metasurfaces show good agreement with the numerical simulations with fitted graphene sheet resistances. The hybrid metasurfaces presented in this work may be deployed in a wide range of applications based on active electromagnetic or optical modulations.
- Published
- 2020
21. Codon usage in Alphabaculovirus and Betabaculovirus hosted by the same insect species is weak, selection dominated and exhibits no more similar patterns than expected
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Ruisheng Yang, Li Qin, Yong Wang, Shenglin Shi, and Yiren Jiang
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0301 basic medicine ,Microbiology (medical) ,Baculoviridae ,food.ingredient ,Insecta ,Neutrality plot ,Genome, Viral ,medicine.disease_cause ,Microbiology ,Genome ,Article ,Evolution, Molecular ,03 medical and health sciences ,food ,Betabaculovirus ,Genetics ,medicine ,Animals ,Selection pressure ,Baculovirus ,Selection, Genetic ,Codon ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics ,ENc plot ,chemistry.chemical_classification ,Mutation ,Base Composition ,biology ,Host (biology) ,biology.organism_classification ,Amino acid ,Synonymous codon usage ,Alphabaculovirus ,030104 developmental biology ,Infectious Diseases ,chemistry ,Codon usage bias ,Host-Pathogen Interactions - Abstract
Mutations shape synonymous codon usage bias in certain organism genomes, while selection shapes it in others. Lepidopteran-specific Alphabaculovirus and Betabaculovirus are two large genera in the family of Baculoviridae. In this study, we analyzed the codon usage patterns in 17 baculoviruses, including 10 alphabaculoviruses and 7 betabaculoviruses, which were isolated from seven insect species, and we characterized the codon usage patterns between Alphabaculovirus and Betabaculovirus. Our results show that all the baculoviruses possessed a general weak trend of codon bias. The differences of ENc (effective number of codons) values, nucleotide contents and the impacts of nucleotide content on ENc value within alpha-/betabaculovirus pairs were independent of whether the host species are the same or different. Furthermore, the majority of amino acid sequences adopted codons unequally in all viruses, but the numbers of common preferred codons between alpha- and betabaculoviruses hosted by the same insect species were not significantly different from the differences observed between alpha- and betabaculoviruses hosted by different insect species. In addition, the amino acids that adopt the same synonymous codon composition between alpha- and betabaculoviruses hosted by the same insect species were statistically as few as those between alpha- and betabaculoviruses hosted by different insect species. Correspondence analysis revealed that no major factors resulted in the codon bias in these baculoviruses, implying multiple minor influential factors exist. Neutrality plot analysis indicated that selection pressure dominated mutations in shaping the codon usage. However, the levels of selection pressure were not significantly different among viruses hosted by the same insect species. We expect that evolution would cause the alpha- and betabaculoviruses hosted by the same insect species to share more patterns, but this effect was not observed., Highlights • The codon usage in Alphabaculovirus and Betabaculovirus is weak biased. • Multiple minor influential factors account for the codon usage. • Selection pressure dominates mutations in shaping the codon usage. • The differences of codon usage within alpha-/betabaculovirus pairs are independent.
- Published
- 2016
22. The First Report of a Fully Sequenced Resistance Plasmid from Shigella boydii
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Yin Zhe, Ruisheng Yang, Jiao Feng, Weijun Chen, Yefeng Qiu, Dongsheng Zhou, Li Wang, Haihong Fang, Fa Yunzhi, Jinglin Wang, Dong Liu, Defu Zhang, and Lei Liu
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0301 basic medicine ,Microbiology (medical) ,Transposable element ,Shigella boydii ,mph(A) ,030106 microbiology ,lcsh:QR1-502 ,Microbiology ,lcsh:Microbiology ,03 medical and health sciences ,Chloramphenicol Resistance ,Complete sequence ,erm(B) ,Antibiotic resistance ,Plasmid ,p2246-CTXM ,medicine ,Original Research ,biology ,bla CTX-M-14 ,biology.organism_classification ,Virology ,Ciprofloxacin ,blaCTX-M-14 ,Mobile genetic elements ,medicine.drug - Abstract
The purpose of this study was to characterize mechanisms of plasmid-mediated antimicrobial resistance in Shigella boydii. S. boydii strain 2246 with resistance to ciprofloxacin, ceftriaxone and azithromycin was isolated from a human case of watery diarrhea in a Chinese public hospital. Resistance in strain 2246 to ceftriaxone and azithromycin was attributable to the presence of blaCTX-M-14, and erm(B) and mph(A), respectively, which were co-located on a multidrug-resistant (MDR) plasmid p2246-CTXM. p2246-CTXM represented a novel IncFII-type MDR plasmid with a very complex chimera structure. Its master backbone was genetically closely related to the R100 plasmid, but p2246-CTXM had evolved to integrate additional R100-unrelated backbone regions as well as massive exogenous mobile elements that carried multiple resistance determinants. In p2246-CTXM, erm(B) together with its leading peptide gene erm(C), mph(A) together with its regulatory genes mrx and mphR(A), and blaCTX-M-14 were captured by three different mobile elements Tn6295, the IS26-mph(A)-mrx-mphR(A)-IS6100 unit, and a truncated ISEcp1-blaCTX-M-14-IS903D-iroN transposition unit, respectively, all of which were harbored in a large Tn3-family transposon Tn6285. p2246-CTXM still carried additional resistance determinants mer (mercury resistance), aacA4 (aminoglycoside resistance), cmlA1 (chloramphenicol resistance), and qacED1 (quaternary ammonium compound resistance). This is the first report of identifying a clinical S. boydii strain simultaneously resistant to ciprofloxacin, ceftriaxone, and azithromycin, and determining the complete sequence of a resistance plasmid from S. boydii.
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- 2016
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23. Octreotide Protects the Mouse Retina against Ischemic Reperfusion Injury through Regulation of Antioxidation and Activation of NF-κB
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Ziqiang Sun, Dongdong Wu, Shaoping Ji, Junsheng Shen, Yanzhang Li, Fang Liu, Jun Wang, Ailing Ji, and Ruisheng Yang
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Aging ,medicine.medical_specialty ,Article Subject ,Cell Survival ,Ischemia ,Apoptosis ,Biology ,Octreotide ,Protective Agents ,medicine.disease_cause ,Biochemistry ,Neuroprotection ,Antioxidants ,Retina ,Mice ,chemistry.chemical_compound ,Retinal Diseases ,Malondialdehyde ,Internal medicine ,medicine ,Animals ,lcsh:QH573-671 ,Ganglion cell layer ,chemistry.chemical_classification ,Reactive oxygen species ,lcsh:Cytology ,Transcription Factor RelA ,Retinal ,Cell Biology ,General Medicine ,Intercellular Adhesion Molecule-1 ,medicine.disease ,Mice, Inbred C57BL ,Disease Models, Animal ,Oxidative Stress ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Reperfusion Injury ,sense organs ,Reactive Oxygen Species ,Reperfusion injury ,Oxidative stress ,Research Article - Abstract
Somatostatin (SST), an endogenous peptide, may exert anti-inflammatory and neuroprotective effects on retinal injury induced by ischemia. Retinal ischemic reperfusion (I/R) injury always produces many reactive oxygen species (ROS), which can aggravate the tissue damage. The effects of octreotide (OCT), a SST analogue, on retinal I/R injury and ROS formation, are not very clear. In this study, we observed the effects of OCT on morphological changes, oxidative stress, and cell death, induced by retinal I/R injury. The activation of nuclear factorκB (NF-κB) and intercellular adhesion molecule-1 (ICAM-1) were further evaluated in I/R retina treated with or without OCT. The retinal layer thickness was increased at 1 day after I/R and decreased at 7 days after I/RP<0.05. This effect was associated with increase in MDA and ROS levelsP<0.05. The Tunel-positive cells increased and the number of ganglion cell layer (GCL) neurons decreased significantly after I/R injury. The expression of p-p65 and ICAM-1 increased significantly in I/R retinasP<0.05. Each effect was markedly attenuated by application of OCT. These data indicate that OCT protects the retina against retinal I/R damage, which could be through inhibition of oxidative stress and downregulation of NF-κB and ICAM-1 expression.
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- 2015
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24. The Neuropilin-1 Inhibitor, ATWLPPR Peptide, Prevents Experimental Diabetes-Induced Retinal Injury by Preserving Vascular Integrity and Decreasing Oxidative Stress
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Ailing Ji, Jun Wang, Fang Liu, Ruisheng Yang, Shaoping Ji, Yanzhang Li, Shuaiwei Wang, Dongdong Wu, and Mengling Li
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Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,lcsh:Medicine ,Vascular permeability ,Biology ,Occludin ,medicine.disease_cause ,Diabetes Mellitus, Experimental ,Mice ,Internal medicine ,Neuropilin 1 ,medicine ,Animals ,lcsh:Science ,Multidisciplinary ,Diabetic Retinopathy ,medicine.diagnostic_test ,lcsh:R ,Retinal Vessels ,Leukostasis ,Extravasation ,Neuropilin-1 ,Mice, Inbred C57BL ,Vascular endothelial growth factor A ,Oxidative Stress ,Endocrinology ,Receptors, Vascular Endothelial Growth Factor ,lcsh:Q ,Oligopeptides ,Oxidative stress ,Electroretinography ,Research Article - Abstract
Neuropilin-1 (NRP-1) is a transmembrane glycoprotein. As a VEGF co-receptor, NRP1 significantly enhances VEGFR2 signaling and promotes vascular permeability and migration. The purpose of this study was to evaluate the effects of an NRP-1 inhibitor, ATWLPPR peptide, on the early stages of diabetic retinopathy. Eight-week-old male C57BL/6 mice were divided into three groups: a Normal group, a Diabetes (DB) ATWLPPR treatment group and a DB saline group. Electroretinography (ERG), fundus fluorescence angiography (FFA) and leukostasis were examined to evaluate the retinal injury induced by diabetes at the end of the fifth week after STZ injection. Occludin expression and extravasation of albumin were measured to determine the extent of vascular injury. The oxidative stress level and the levels of inflammation-associated proteins were also assayed. The results indicated that treatment with ATWLPPR prevents the abnormal condition of ERG (amplitudes of b-wave decreased and implicit time increased) and vascular injury (occludin degradation and increase in extravasated albumin). These effects were associated with a reduction in the oxidase stress level and the expression of VEGF, GFAP, and ICAM-1. We conclude that ATWLPPR, an NRP-1 inhibitor, may reduce the early retinal damage induced by diabetes by preserving vascular integrity and decreasing the oxidative stress level. Blockade of NRP-1 may be a new therapeutic strategy for the early stages of DR.
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- 2015
25. Non-vacuum Deposition Methods for Thin Film Solar Cell: Review.
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Ruisheng Yang, Mazalan, Elham, Chaudhary, Kashif Tufail, Haider, Zuhaib, and Ali, Jalil
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THIN film devices , *SOLAR cells , *SOLAR energy , *EMISSIONS (Air pollution) , *RENEWABLE energy sources - Abstract
Solar power is a promising abundant, pollution free, inexhaustible and clean source of energy. Development of cost-effective solar system with high conversion efficiency is the key challenge in field of solar panel manufacturing industry. Different non-vacuum deposition methods have been developed to reduce the cost of solar panel system along with high conversion efficiency. In this paper, a review is presented with major focus on three non-vacuum deposition methods, as spin coating, dip coating and spray coating. Each mentioned deposition technique is discussed in details along with role of different deposition parameters on the characteristics of grown solar thin films. [ABSTRACT FROM AUTHOR]
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- 2017
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26. Occludin downregulation in high glucose is regulated by SSTR2 via the VEGF/NRP1/Akt signaling pathway in RF/6A cells.
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MENGLING LI, SHUAIWEI WANG, SONGJIANG WANG, LEI ZHANG, DONGDONG WU, RUISHENG YANG, AILING JI, YANZHANG LI, and JUN WANG
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DOWNREGULATION ,OCCLUDINS ,GLUCOSE ,CELL communication ,SOMATOSTATIN receptors ,VASCULAR endothelial growth factors - Abstract
Occludin is a tight junction protein that forms the permeability barrier, which is typically disturbed in ischemic associated diseases. The aim of the present study was to determine whether somatostatin receptor 2 (SSTR2) in RF/6A cells is involved in the modulation of the downregulation of occludin induced by high glucose, and to evaluate the implicated molecules. RF/6A cells were maintained in Dulbecco's modified Eagle medium and treated with 0 or 30 mM D-glucose. SSTR
2 agonist octreotide (OCT), OCT with SSTR2 antagonist cycle-somatostatin (c-SOM) and neuropilin 1 (NRP1) inhibitor ATWLPPR, respectively, were administered to RF/6A cells under high glucose conditions. Cell apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling. Western blot analysis was used to detect the protein expression level of SSTR2, occludin, vascular endothelial growth factor (VEGF), protein kinase B (Akt), phosphorylated Akt (p-Akt), extracellular signal-related kinases (ERK) and p-ERK proteins. The amount of VEGF released was determined by ELISA. Notably, the level of occludin reduced significantly under high glucose conditions. The results indicated that the administration of OCT prevented the reduction of occludin induced by high glucose, and co-administration with c-SOM reversed the effect of OCT. Increased VEGF secretion and expression of VEGF, p-Akt and p-ERK in RF/6A cells induced by high glucose were inhibited by OCT. ATWLPPR also prevented the downregulation of occludin, but did not inhibit p-Akt and p-ERK levels under high glucose conditions. The current study concluded that the activation of SSTR2 prevents high glucose-induced occludin downregulation in RF/6A cells, and VEGF, NRP1, p-Akt and p-ERK were implicated in this process. The pharmacological effects of SSTR2 targeting to endothelium may be used to assess the role of resistance of permeability and anti-inflammation. [ABSTRACT FROM AUTHOR]- Published
- 2017
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27. Weak coupling between bright and dark resonators with electrical tunability and analysis based on temporal coupled-mode theory.
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Quanhong Fu, Fuli Zhang, Yuancheng Fan, Jiajia Dong, Weiqi Cai, Wei Zhu, Shuang Chen, and Ruisheng Yang
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ELECTRIC resonators ,ELECTROMAGNETIC induction ,QUANTUM theory ,PHOTORESISTORS ,SUPERCONDUCTORS - Abstract
We investigate the electrically tunable Electromagnetic induced transparency (EIT)-like effect of active metamaterial structures composed of a wire and a split ring resonator by the simulation, experiment, and temporal coupled-mode theory. It is illustrated that an EIT-like effect appears as a result of weak coupling between bright and dark resonators. Around the EIT-like peak frequency, the superradiant resonance mode of the bright resonator is highly suppressed by the subradiant resonance mode of the dark resonator, and high transmittance as well as large group delay is manifested. By integrating a varactor diode into the EIT structure and altering the bias voltage, the EIT-like effect can be dynamically tuned. As the bias voltage ranges from 0V to 8V, the EIT-like peak frequency exhibits a prominent blueshift of 0.22 GHz and the transmittance experiences a modulation with a modulation depth up to 98%. Using the temporal coupled-mode theory, the transmission spectrum of the EIT structure is predicted and the parameters of the resonator system are retrieved. [ABSTRACT FROM AUTHOR]
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- 2017
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28. The First Report of a Fully Sequenced Resistance Plasmid from Shigella boydii.
- Author
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Li Wang, Lei Liu, Dong Liu, Zhe Yin, Jiao Feng, Defu Zhang, Haihong Fang, Yefeng Qiu, Weijun Chen, Ruisheng Yang, Jinglin Wang, Yunzhi Fa, and Dongsheng Zhou
- Subjects
PLASMIDS ,SHIGELLA ,DRUG resistance in bacteria - Abstract
The purpose of this study was to characterize mechanisms of plasmid-mediated antimicrobial resistance in Shigella boydii. S. boydii strain 2246 with resistance to ciprofloxacin, ceftriaxone and azithromycin was isolated from a human case of watery diarrhea in a Chinese public hospital. Resistance in strain 2246 to ceftriaxone and azithromycin was attributable to the presence of bla
CTX--M--14 and erm(B) and mph(A), respectively, which were co-located on a multidrug-resistant (MDR) plasmid p2246-CTXM. p2246-CTXM represented a novel IncFII-type MDR plasmid with a very complex chimera structure. Its master backbone was genetically closely related to the R100 plasmid, but p2246-CTXM had evolved to integrate additional R100-unrelated backbone regions as well as massive exogenous mobile elements that carried multiple resistance determinants. In p2246-CTXM, erm(B) together with its leading peptide gene erm(C), mph(A) together with its regulatory genes mrx and mphR(A), and blaCTX--M--14 were captured by three different mobile elements Tn6295, the IS26-mph(A)-mrxmphR( A)-IS6100 unit, and a truncated ISEcp1-blaCTX--M--14 IS-903D-iroN transposition unit, respectively, all of which were harbored in a large Tn3-family transposon Tn6285. p2246-CTXM still carried additional resistance determinants mer (mercury resistance), aacA4 (aminoglycoside resistance), cmlA1 (chloramphenicol resistance), and qacED1 (quaternary ammonium compound resistance). This is the first report of identifying a clinical S. boydii strain simultaneously resistant to ciprofloxacin, ceftriaxone, and azithromycin, and determining the complete sequence of a resistance plasmid from S. boydii. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
29. Complete sequences of KPC-2-encoding plasmid p628-KPC and CTX-M-55-encoding p628-CTXM coexisted in Klebsiella pneumoniae.
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Li Wang, Haihong Fang, Jiao Feng, Zhe Yin, Xiaofang Xie, Xueming Zhu, Jie Wang, Weijun Chen, Ruisheng Yang, Hong Du, Dongsheng Zhou, Yoshikazu Ishii, and García-Fernández, Aurora
- Subjects
PLASMIDS ,KLEBSIELLA pneumoniae ,NUCLEOTIDE sequence - Abstract
A carbapenem-resistant Klebsiella pneumoniae strain 628 was isolated from a human case of intracranial infection in a Chinese teaching hospital. Strain 628 produces KPC-2 and CTX-M-55 encoded by two different conjugative plasmids, i.e., the IncFII
K plasmid p628-KPC and the IncI1 plasmid p628-CTXM respectively. blaKPC-2 is captured by a Tn1722-based unit transposon with a linear structure. ΔTn3-ISKpn27-blaKPC-2- ΔISKpn6-ΔTn1722 and this transposon together with a mercury resistance (mer) gene locus constitutes a 34 kb acquired drug-resistance region. blaKPC-2 has two transcription starts (nucleotides G and C located at 39 and 250 bp upstream of its coding region respectively) which correspond to two promoters, i.e., the intrinsic P1 and the upstream ISKpn27/Tn3-provided P2 with the core -35/-10 elements TAATCC/TTACAT and TTGACA/AATAAT respectively. blaCTX-M-55 is mobilized in an ISEcp1-blaCTX-M-55- 1orf477 transposition unit and appears to be the sole drug-resistant determinant in p628-CTXM. blaCTX-M-55 possesses a single transcription start (nucleotides G located at 116 bp upstream of its coding region) corresponding to the ISEcp1-provided P1 promoter with the core -35/-10 element TTGAAA/TACAAT. All the above detected promoters display a characteristic of constitutive expression. Coexistence of blaKPC and blaCTX-M in K. pneumoniae has been reported many times but this is the first report to gain deep insights into genetic platforms, promoters, and expression of the two coexisting bla genes with determination of entire nucleotide sequences of the two corresponding plasmids. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
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