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Ashish S, Kalluraya P, Pai M, Murlimanju B, Rao Y, Prabhu L, Agrawal A. Morphometric study of the lumbar vertebrae in dried anatomical collections. F1000Res 2023; 11:1408. [PMID: 37990689 PMCID: PMC10660310 DOI: 10.12688/f1000research.126879.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/29/2023] [Indexed: 11/23/2023] Open
Abstract
Background The objective of this anatomical study was to perform the morphometry of dried lumbar vertebrae in human cadavers. Methods This study utilized 200 adult human cadaveric dried lumbar vertebrae. The digital Vernier calipers was used to perform the measurements. The height, antero-posterior length, transverse length of the body of the vertebrae, interpedicular distance at the lateral ends, lamina length, height and thickness, superior and inferior articular facet height and width, mid sagittal and transverse diameter of vertebral foramen, height, width and thickness of the pars inter-articularis were measured. Results The vertebral body's anteroposterior length was more at the lower border than at the superior border ( p < 0.01). The length of lamina was higher over the right in comparison to the left (p < 0.001). The height of lamina, width of inferior articular facet, diameter of lateral recess and thickness of pars inter-articularis were greater for the left sided specimens ( p < 0.01). The statistical significance was not observed for the comparison of the remaining parameters ( p > 0.05). Conclusion This anatomical study offered several dimensions of lumbar vertebrae, which are essential in the surgical practice. The implants at the lumbar vertebrae need to be manufactured based on the anatomical dimensions of that particular sample population.
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Affiliation(s)
- Sharad Ashish
- Department of Anatomy, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India
| | - P. Kalluraya
- Department of Anatomy, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India
| | - Mangala Pai
- Department of Anatomy, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India
| | - B.V. Murlimanju
- Department of Anatomy, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India
| | - Y. Rao
- Department of Anatomy, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India
| | - Latha Prabhu
- Department of Anatomy, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Manipal, India
| | - Amit Agrawal
- Department of Neurosurgery, All India Institute of Medical Sciences, Bhopal, Madhya Pradesh, 462020, India
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Wang X, Huang Z, Li C, Liu M, Yang G, Luo L, Rao Y, Shen Y, Wang J. Biological Characteristics of Beauveria majiangensis Strain MJ1015 and Optimization of Solid Medium Technology for Sporulation. Pol J Microbiol 2023; 72:377-389. [PMID: 37817297 PMCID: PMC10725162 DOI: 10.33073/pjm-2023-033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/24/2023] [Indexed: 10/12/2023] Open
Abstract
The entomopathogenic fungus Beauveria majiangensis strain MJ1015, recently isolated from white grubs on a blueberry farm in Guizhou, China, could be used as a biocontrol agent. As a first step toward determining the effect of different solid culture media, temperature, and pH on colony growth rate and sporulation, we evaluated the optimum solid medium for mycelial growth and conidia production on a commercial scale. Subsequently, we also used single-factor analysis and response surface optimization to optimize the composition of the solid culture medium. On potato dextrose agar (PDA) medium, MJ1015 grew fastest and produced the highest spore yield at 29°C and pH 5. The best solid medium for the growth and sporulation of strain MJ1015 comprised 64.70 g/l of rice, 13.00 g/l of wheat, 0.30 g/l of NaNO3, 0.36 g/l of K2HPO4 · 3H2O, and 1.00 g/l of CaCO3. Rice, NaNO3, and K2HPO4 · 3H2O were the main influencing factors. The predicted value of cultured spores using the optimal medium was 4.56 x 1010 conidia/l. The validation test results showed that the average growth rate of strain MJ1015 on the optimal medium was 85% and 96% faster than that on Sabouraud dextrose agar with yeast extracts medium (SDAY) and PDA, respectively. Sporulation was 43.90 times and 9.65 times of that produced on SDAY and PDA, respectively. Our findings provide a theoretical basis for the commercial production of B. majiangensis to control white grubs.
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Affiliation(s)
- Xinghong Wang
- Guizhou Institute of Biology, Guiyang, Guizhou, China
| | | | - Congchun Li
- Guangrao Vocational School of Secondary Technical Education, Dongying, China
| | - Man Liu
- Guizhou Institute of Biology, Guiyang, Guizhou, China
| | | | - Lilin Luo
- Guizhou Institute of Biology, Guiyang, Guizhou, China
| | - Yongchao Rao
- Guizhou Institute of Biology, Guiyang, Guizhou, China
| | - Yan Shen
- Guizhou Institute of Biology, Guiyang, Guizhou, China
| | - Jing Wang
- Guizhou Institute of Biology, Guiyang, Guizhou, China
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Rao Y, Hu Y, Wang S, Zhao S, Zhou S. Numerical Simulation Study on the Flow Field and Separation Efficiency by Built-In Twisted Tape in the Hydrocyclone. ACS Omega 2023; 8:26301-26316. [PMID: 37521627 PMCID: PMC10373205 DOI: 10.1021/acsomega.3c02549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 06/29/2023] [Indexed: 08/01/2023]
Abstract
Aiming at the separation of mud and sand in natural gas hydrate, for the designed built-in twisted tape hydrocyclone, the numerical simulation method was used to study the effects of different types of built-in twisted tape and operating conditions on the internal flow field of the hydrocyclone, separation efficiency, and influence of hydrate particle size distribution. The research results show that the built-in twisted tape has the same swirling direction as the hydrocyclone, which is beneficial to improving the swirling intensity, and the ability to carry and separate solid particles is obviously enhanced. The built-in twisted tape hydrocyclone with a length of 300 mm has better separation efficiency and internal flow field stability. By changing the conditions of the inlet velocity and the initial concentration of hydrate particles, the comparison shows that when the inlet velocity is 8 m/s, the volume of mud and sand is 25%, the initial concentration of hydrate particles is 15%, and the built-in tape is 300 mm long. The tape hydrocyclone has the best separation efficiency. Compared with the basic hydrocyclone, the built-in twisted tape hydrocyclone with a length of 300 mm increases the separation efficiency of mud and sand by 7.49%, while the pressure drop only increases by 2.67%, showing the superiority of the built-in twisted tape structure.
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Affiliation(s)
- Yongchao Rao
- Jiangsu
Key Laboratory of Oil−Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum and Gas Engineering, School of Energy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Yong Hu
- Jiangsu
Key Laboratory of Oil−Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum and Gas Engineering, School of Energy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Shuli Wang
- School
of Energy, Quanzhou Vocational and Technical
University, Quanzhou, Fujian 362268, China
| | - Shuhua Zhao
- Jiangsu
Key Laboratory of Oil−Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum and Gas Engineering, School of Energy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Shidong Zhou
- Jiangsu
Key Laboratory of Oil−Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum and Gas Engineering, School of Energy, Changzhou University, Changzhou, Jiangsu 213164, China
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4
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Rao Y, Qi X, Peng Q, Chen Y, Gong X, Xie R, Zhong W. Flower-like NiO to flower-like NiO/Ni@C microspheres: An effective strategy to comprehensively improve the loss capabilities. J Colloid Interface Sci 2023; 629:981-993. [DOI: 10.1016/j.jcis.2022.09.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/20/2022] [Accepted: 09/04/2022] [Indexed: 11/28/2022]
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Barbera JA, Kiely D, Gruenig E, Balasubramanian V, Vizza CD, Elwing J, Sood N, Rao Y, Holdstock L, Seaman S, Broderick M, White RJ. Efficacy and dose-response relationship of oral treprostinil in PAH patients on monotherapy or dual background therapy. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.1920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
FREEDOM-C and FREEDOM-C2 were randomized, placebo-controlled, double-blinded international, multicenter studies investigating the use of oral treprostinil (TRE) in subjects on mono or dual background pulmonary arterial hypertension (PAH) therapies. Both had a primary endpoint of change in 6-minute walk distance (6MWD) at Week 16 vs baseline. Previous post-hoc analyses combining mono and dual therapy subjects (PDE-5i and/or ERA) from these studies revealed a TRE dose-dependent increase in 6MWD. (1. White & Rao, 2016)
Purpose
This post-hoc analysis was performed to determine if subjects from FREEDOM-C and FREEDOM-C2 derive improvements in 6MWD with increasing doses of TRE when stratified by mono or dual background therapy and to determine if PAH background therapies (mono or dual) impacted 6MWD.
Methods
All active subjects (n=331) from FREEDOM-C and FREEDOM-C2 were grouped into TRE dose tertiles (low-dose: ≤2 mg BID, mid-dose: >2 mg to ≤3.5 mg BID, and high-dose: >3.5 mg BID). Placebo subjects (n=329) were in a separate 0 mg dose group. No data imputation was implemented.
Comparisons of 6MWD change at Weeks 4, 8, 12, and 16 between mono and dual therapy subgroups at any dose group were performed using a two-sample t-test or nonparametric Wilcoxon rank-sum test. The nonparametric Kruskal-Wallis test was conducted with subsequent pairwise comparisons of 6MWD change at Week 16 between the four dose groups through Dunn's approach. Additionally, the Jonckheere-Terpstra test was used to assess the linear trend for 6MWD improvement with higher doses of TRE.
Results
Baseline characteristics of the combined intention to treat (ITT) population and summary of 6MWD for subjects with both baseline and Week 16 data are in Table 1. 6MWD change improved steadily to Week 16 in subjects at higher TRE doses, regardless of the number of PAH background therapies (Figure 1). No statistical differences were found between mono and dual therapy at any time point or for any dose group. At Week 16, there was a significant difference in 6MWD change between the placebo group and high dose group within both mono and dual background therapy subjects. The difference between the low- and high-dose groups was significant for subjects on dual background therapy. There was a significant positive linear trend for TRE doses in 6MWD improvement at Week 16 for both monotherapy subjects (one-sided p-value = 0.0002) and dual therapy subjects (one-sided p-value = 0.0242).
Conclusions
6MWD improved in PAH patients regardless of their background therapy (monotherapy or dual background) and derive greater 6MWD improvements with higher doses of TRE. The observed dose-dependent 6MWD increase supports the use of TRE in sequential combination with background therapies (mono or dual).
Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): United Therapeutics Corporation
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Affiliation(s)
- J A Barbera
- Hospital Clinic de Barcelona , Barcelona , Spain
| | - D Kiely
- Sheffield Teaching Hospitals NHS Trust , Sheffield , United Kingdom
| | - E Gruenig
- Thoracic Clinic-Heidelberg , Heidelberg , Germany
| | - V Balasubramanian
- University of California San Francisco , Fresno , United States of America
| | - C D Vizza
- Sapienza University of Rome , Rome , Italy
| | - J Elwing
- University of Cincinnati Medical Center , Cincinnati , United States of America
| | - N Sood
- University of California , Davis , United States of America
| | - Y Rao
- United Therapeutics Corporation , Research Triangle Park , United States of America
| | - L Holdstock
- United Therapeutics Corporation , Research Triangle Park , United States of America
| | - S Seaman
- United Therapeutics Corporation , Research Triangle Park , United States of America
| | - M Broderick
- United Therapeutics Corporation , Research Triangle Park , United States of America
| | - R J White
- University of Rochester Medical Center , Rochester , United States of America
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Rao Y, Wang S, Li L. Numerical Simulation of the Flow Pattern of Spiral Annular Flow with a Guide Strip by Spiral On-Way. ACS Omega 2022; 7:31961-31973. [PMID: 36120054 PMCID: PMC9475622 DOI: 10.1021/acsomega.2c02924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
To study the gas-liquid two-phase spiral annular flow pattern and its conversion law in a horizontal tube with twist tape by spiral on-way, a numerical simulation is carried out using the RNG k-ε model, and the DPM model is adopted as the particle motion model. The research results show that three main flow patterns are obtained, which are spiraling churn flow, spiraling annular flow, and spiraling annular twine flow. The ratio of the liquid-phase to gas-phase velocity V L/V G is the main factor that affects the existence of the gas phase. When V L/V G > 1/2, the flow pattern is a spiral cluster flow; when 1/5 < V L/V G< 1/2, the flow pattern is a spiral annular flow; and when V L/V G < 1/5, the flow pattern is a spiral annular flow. Compared with the flow pattern of the local spiral flow pattern of the short twisted band, it was found that the occurrence conditions of annular flow were postponed and a new flow pattern appeared. The research results of this paper have guiding significance for the pipeline risk management of natural gas hydrates and the engineering application of the full rotation of guide strips.
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Affiliation(s)
- Yongchao Rao
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum Engineering, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Shuli Wang
- School
of Energy, Quanzhou Vocational and Technical
University, Quanzhou, Fujian 362268, China
| | - Lijun Li
- China
Petroleum & Chemical Corporation North China Oil & Gas Company, Zhengzhou, Henan 450006, China
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7
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Podila K, Chen Q, Huang X, Li C, Rao Y, Waddington G, Jafri T. Coupled simulations for prismatic gas-cooled reactor. Nuclear Engineering and Design 2022. [DOI: 10.1016/j.nucengdes.2022.111858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Luo Y, Rao Y, Gu X, Chai P, Yang Y, Lin J, Xu X, Jia R, Xu S. Novel MSH6 mutation predicted metastasis in eyelid and periocular squamous cell carcinoma. J Eur Acad Dermatol Venereol 2022; 36:2331-2342. [PMID: 35855666 DOI: 10.1111/jdv.18454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 06/03/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Our previous research revealed the relative local aggressiveness of eyelid and periocular squamous cell carcinoma (EPSCC), but its distinct genetic characteristics involved remain unknown. OBJECTIVES We conducted this study based on next-generation sequencing to identify the genetic distinctiveness of EPSCC and damaging mutations for possible etiology and poor prognosis. METHODS We performed sequencing using a 556-gene panel (smartonco) in 48 EPSCCs. Cox hazards model was applied to explore mutated genes that increase risk of metastasis and death. Pathogenesis of the mutations was predicted by sequence alignment algorithms. RESULTS The most commonly mutated genes were KMT2C (N=17, 35%), LRP1B (N=14, 29%), KMT2D (N=12, 25%), PTCH1(N=10, 21%) and TP53(N=10, 21%). DNA mismatch repair (MMR) genes (42%) like MSH6(19%) and MLH3(12%) were among the most frequently mutated genes. Cell cycle regulators including TP53(21%) and CDKN2A (10%) were less frequently mutated than in other squamous cell carcinomas (SCCs). Ultra violet exposure, MMR deficiency and aging were the main etiology. Of note, KMT2C has a deleterious mutation hotspot. Patients burdened with MSH6 mutation has a higher risk of overall metastasis (P=0.045, HR=5.165) and nodal metastasis (P=0.022, HR=14.038). Moreover, a hotspot mutation MSH6E52A brought an even higher risk of nodal metastasis (P=0.011, HR=18.745). CONCLUSIONS EPSCCs displayed a unique mutation profile from cutaneous SCCs and mucosal SCCs. We have identified novel damaging mutations in epigenetic regulators like KMT2C boosted early onset of EPSCCs in addition to UVR, aging or MMR deficiency. And malfunction of MMR genes worsened prognosis.
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Affiliation(s)
- Y Luo
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Y Rao
- Department of pathology, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - X Gu
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - P Chai
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Y Yang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - J Lin
- Department of pathology, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - X Xu
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - R Jia
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - S Xu
- Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
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Zheng X, Chen Z, Wu X, LI X, Xie Y, Wu J, Xiao M, Cao S, Wei Q, Zhu W, Rao Y, Chen Q, Wen Y, Gu J. POS1002 DIAGNOSTIC DELAY AND ITS ASSOCIATED FACTORS IN CHINESE AXIAL SPONDYLOARTHRITIS: A RETROSPECTIVE STUDY. Ann Rheum Dis 2022. [DOI: 10.1136/annrheumdis-2022-eular.4612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BackgroundFew data on the prolonged diagnosis and its associated factors in Chinese axial spondyloarthritis (axSpA) is available.ObjectivesTo delineate the landscape of diagnostic delay in Chinese axSpA, investigate its associated factors and explore its potential impact on medication modalities.MethodsA total of 1,295 patients fulfilling the ASAS classification criteria were obtained. Demographic and clinical data were collected through predesigned questionnaires and available medical records. Logistic regression analyses in univariate and multivariable model were performed, using the median of diagnostic delay as cut-off point for group classification. Differences between early and late diagnosed group were subsequently compared by the Pearson chi-square test or Mann-Whitney U test.ResultsThe median (IQR) diagnostic delay in Chinese axSpA was 3.0 (1.0~7.0) years and 24.8% of them reported a history of misdiagnosis. Older age at onset (OR=0.97, P<0.001) and higher education attainment (P=0.001) were correlated with early diagnosis of axSpA, whereas coming from less developed areas (P=0.002), a history of peripheral arthritis at the time of diagnosis (OR=1.58, P=0.002) and history of misdiagnosis (OR=1.98, P<0.001) increased the risk of diagnostic delay. Medication modalities were similar between two groups, but the proportion with no medication ever and percentage without regular medication in recent 3 months were higher in the late diagnosed group than early group (26.5% vs. 20.7%, P=0.02; 34.7% vs. 28.6%, P=0.02).ConclusionOur findings depicted a detailed spectrum of diagnostic delay in Chinese axSpA, verified five associated factors and pinpointed a remarkable treatment delay even after diagnosis, especially in late diagnosis group.References[1]Masson Behar V, Dougados M, Etcheto A, Kreis S, Fabre S, Hudry C, et al. Diagnostic delay in axial spondyloarthritis: A cross-sectional study of 432 patients. Joint bone spine. 2017;84(4):467-71.Figure 1.Cumulative distribution of age at onset and age at diagnosis in Chinese axSpA(A) the entire group. (B) stratified by early and late diagnosed group. (C) stratified by education level (college, middle school, secondary school). (D) stratified by history of peripheral arthritis when diagnosed. (E) stratified by history of misdiagnoses when diagnosed. (F) stratified by native place, as statistical significance was found between eastern coastal and western China, only these two groups were presented.Disclosure of InterestsNone declared
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Rao Y, Liu Z, Wang S, Li L. Experimental Study on Hydrate Safe Flow in Pipelines under a Swirl Flow System. ACS Omega 2022; 7:16629-16643. [PMID: 35601304 PMCID: PMC9118381 DOI: 10.1021/acsomega.2c00892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 04/21/2022] [Indexed: 06/15/2023]
Abstract
With the development of oil and gas resources gradually extending to the deep sea, the blockage of gas hydrate is attracting more and more attention. How to inhibit hydrate blockage efficiently and economically in oil and gas gathering transportation pipelines and ensure the safe operation has become a hot and difficult point in the field of oil and gas gathering and transportation research. At present, the research on the safe flow of gas hydrate is still in the exploratory stage, and applying swirl flow to hydrate risk control technology has a great engineering application value. A systematic experimental study on the safe flow of gas hydrate in a swirl flow system is carried out herein. The experimental results show the following: (1) The laws of gas hydrate flow, transport, deposition, and pipe plugging under various experimental conditions of the swirl flow system are obtained, the safe flow region of hydrate under the swirl flow system in the pipeline is obtained, and the safe flow boundary of hydrate is expanded. (2) Beginning with the theoretical analysis of the safe flow of gas hydrate in a pipeline, the flow characteristics of gas hydrate in the flow system are described; the special flow form of swirl flow has a great influence on the safe flow law of hydrate. (3) The growth and coalescence mechanisms of spiral hydrate in two mainstream systems of separated flow and dispersed flow are explored and researched. The critical tangential velocity of flow is taken as the standard of criterion.
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Affiliation(s)
- Yongchao Rao
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou 213164, Jiangsu, China
- School
of Petroleum Engineering, Changzhou University, Changzhou 213164, Jiangsu, China
| | - Zehui Liu
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou 213164, Jiangsu, China
- School
of Petroleum Engineering, Changzhou University, Changzhou 213164, Jiangsu, China
| | - Shuli Wang
- School
of Energy, Quanzhou Vocational and Technical
University, Quanzhou 362268, Fujian, China
| | - Lijun Li
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou 213164, Jiangsu, China
- School
of Petroleum Engineering, Changzhou University, Changzhou 213164, Jiangsu, China
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11
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Rao Y, Long L, Jing T, Qi X, Peng Q, Gong X, Chen Y, Xie R, Zhong W, Du Y. Magnetic modulation of core@shell MoS 2-based flower-like multicomponent nanocomposites to improve microwave attenuation. J Colloid Interface Sci 2022; 608:2387-2398. [PMID: 34763891 DOI: 10.1016/j.jcis.2021.10.138] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 10/15/2021] [Accepted: 10/24/2021] [Indexed: 01/14/2023]
Abstract
Nanocomposites with a three-dimensional (3D) flower-like geometrical morphology were considered as excellent microwave absorbers (MAs) because of the numerous effective sites for the multiple reflections of electromagnetic (EM) wave. Herein, for optimizing the EM matching characteristic and taking full advantage of interface polarization, a strategy of magnetic modulation was proposed to further improve the EM wave absorption performances (EMWAPs) of MoS2-based nanocomposites. We adopted a simple hydrothermal route and a combined method of hydrothermal treatment/hydrogen reduction to synthesize core@shell CoFe2O4@MoS2 and CoFe@MoO2/MoS2 flower-like nanocomposites, respectively. The obtained results indicated that the hydrogen reduction effectively improved their magnetic properties and magnetic loss capabilities, and their 3D flower-like geometrical morphologies were well maintained during the hydrogen reduction process. The obtained core@shell CoFe@MoO2/MoS2 flower-like nanocomposites presented the extraordinary comprehensive EMWAPs including the optimal reflection loss value of -54.83 dB with the matching thicknesses (dm) value of 2.05 mm and effective absorption bandwidth value of 6.40 GHz with the dm value of 2.59 mm, which were evidently superior to the properties of CoFe2O4@MoS2. Therefore, the findings provided an effective pathway to further improve EMWAPs of MoS2-based core@shell nanocomposites and the as-prepared core@shell CoFe@MoO2/MoS2 flower-like nanocomposites could be utilized as the novel high-efficient MAs.
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Affiliation(s)
- Yongchao Rao
- College of Physics, Guizhou Province Key Laboratory for Photoelectrics Technology and Application, Guizhou University, Guiyang City 550025, People's Republic of China
| | - Lin Long
- College of Physics, Guizhou Province Key Laboratory for Photoelectrics Technology and Application, Guizhou University, Guiyang City 550025, People's Republic of China
| | - Tao Jing
- College of Science, Kaili University, Kaili 556011, People's Republic of China
| | - Xiaosi Qi
- College of Physics, Guizhou Province Key Laboratory for Photoelectrics Technology and Application, Guizhou University, Guiyang City 550025, People's Republic of China; National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093, People's Republic of China.
| | - Qiong Peng
- College of Physics, Guizhou Province Key Laboratory for Photoelectrics Technology and Application, Guizhou University, Guiyang City 550025, People's Republic of China
| | - Xiu Gong
- College of Physics, Guizhou Province Key Laboratory for Photoelectrics Technology and Application, Guizhou University, Guiyang City 550025, People's Republic of China
| | - Yanli Chen
- College of Physics, Guizhou Province Key Laboratory for Photoelectrics Technology and Application, Guizhou University, Guiyang City 550025, People's Republic of China
| | - Ren Xie
- College of Science, Kaili University, Kaili 556011, People's Republic of China
| | - Wei Zhong
- National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093, People's Republic of China.
| | - Youwei Du
- National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093, People's Republic of China
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Rao Y, Liu Z, Wang S, Li L. Numerical Simulation on the Flow Pattern of a Gas-Liquid Two-Phase Swirl Flow. ACS Omega 2022; 7:2679-2689. [PMID: 35097266 PMCID: PMC8793073 DOI: 10.1021/acsomega.1c05144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
The gas-liquid contact area can be increased by the gas-liquid swirl flow, and the heat and mass transfer efficiency between gas and liquid can be enhanced by the gas-liquid swirl flow. The gas hydrate formation can be promoted by the swirl flow. The swirl flow can ensure the safety of the natural gas hydrate slurry. The flow pattern and conversion law of gas-liquid swirl with a twist tape should be investigated, and numerical simulation has been carried out by using the Reynolds stress model and the level set model. As a result, four different flow patterns are obtained, namely, swirl-stratified flow, swirl bubble flow, swirl slug flow, and swirl annular flow. The influence of gas-liquid-phase velocity on the flow pattern is investigated. The drag force generated by the two-phase slip velocity can change the gas form. At the same time, the flow pattern at different positions of the pipe will also change because of the attenuation of the swirl flow. Finally, the flow pattern map of the gas-liquid swirl flow is accomplished, and it is compared with the Mandhane flow pattern map. The flow boundary of the swirl bubble flow and the swirl annular flow is predicted.
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Affiliation(s)
- Yongchao Rao
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum Engineering, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Zehui Liu
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum Engineering, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Shuli Wang
- School
of Energy, Quanzhou Vocational and Technical
University, Quanzhou, Fujian 362268, China
| | - Lijun Li
- Jiangsu
Key Laboratory of Oil-Gas Storage and Transportation Technology, Changzhou University, Changzhou, Jiangsu 213164, China
- School
of Petroleum Engineering, Changzhou University, Changzhou, Jiangsu 213164, China
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Jian H, Zu P, Rao Y, Li W, Mou T, Lin J, Zhang F. Comparative analysis of melanin deposition between Chishui silky fowl and Taihe silky fowl. Journal of Applied Animal Research 2021. [DOI: 10.1080/09712119.2021.1981911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Huafeng Jian
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, The Ministry of Education, Guizhou University, Guiyang, People’s Republic of China
- Guizhou Province Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science, Guizhou University, Guiyang, People’s Republic of China
- Research Institute of Poultry, Guizhou University, Guiyang, People’s Republic of China
- Guizhou University Science and Research Poultry Farm, Guiyang, People’s Republic of China
| | - Panyu Zu
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, The Ministry of Education, Guizhou University, Guiyang, People’s Republic of China
- Guizhou Province Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science, Guizhou University, Guiyang, People’s Republic of China
- Research Institute of Poultry, Guizhou University, Guiyang, People’s Republic of China
- Guizhou University Science and Research Poultry Farm, Guiyang, People’s Republic of China
| | - Yongchao Rao
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, The Ministry of Education, Guizhou University, Guiyang, People’s Republic of China
- Guizhou Province Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science, Guizhou University, Guiyang, People’s Republic of China
- Research Institute of Poultry, Guizhou University, Guiyang, People’s Republic of China
- Guizhou University Science and Research Poultry Farm, Guiyang, People’s Republic of China
| | - Wei Li
- Guizhou Province Management Station of Livestock Genetic Resources, Guiyang, People’s Republic of China
| | - Tenghui Mou
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, The Ministry of Education, Guizhou University, Guiyang, People’s Republic of China
- Guizhou Province Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science, Guizhou University, Guiyang, People’s Republic of China
- Research Institute of Poultry, Guizhou University, Guiyang, People’s Republic of China
- Guizhou University Science and Research Poultry Farm, Guiyang, People’s Republic of China
| | - Jiadong Lin
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, The Ministry of Education, Guizhou University, Guiyang, People’s Republic of China
- Guizhou Province Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science, Guizhou University, Guiyang, People’s Republic of China
- Research Institute of Poultry, Guizhou University, Guiyang, People’s Republic of China
- Guizhou University Science and Research Poultry Farm, Guiyang, People’s Republic of China
| | - Fuping Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, The Ministry of Education, Guizhou University, Guiyang, People’s Republic of China
- Guizhou Province Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science, Guizhou University, Guiyang, People’s Republic of China
- Research Institute of Poultry, Guizhou University, Guiyang, People’s Republic of China
- Guizhou University Science and Research Poultry Farm, Guiyang, People’s Republic of China
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He YJ, Wang YQ, Tang HR, He M, Rao Y, Zhou R, Wang JL. [Clinical efficacy and pregnancy outcomes of fertility-preserving re-treatment after recurrence of the patient with atypical endometrial hyperplasia and early stage endometrial carcinoma]. Zhonghua Fu Chan Ke Za Zhi 2020; 55:21-28. [PMID: 32074769 DOI: 10.3760/cma.j.issn.0529-567x.2020.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the clinical efficacy and pregnancy outcomes of fertility- preserving re-treatment in patients with recurrent atypical endometrial hyperplasia (AEH) and early stage endometrial carcinoma (EEC) after achieved complete remission (CR) of primary fertility-preserving therapy. Methods: There were 104 cases of AEH and EEC collected from 9 hospitals in the multi-center research network platform of fertility-preserving therapy of endometrial carcinoma in China from January 2005 to May 2019. Thirth-one cases of them relapsed from four hospitals mentioned above,who achieved CR after primary fertility-preserving therapy,was analyzed retrospectively. Of the 31 cases, 27 cases chose fertility-preserving re-treatment. The demographic characteristics, re-treatment effect, clinical factors and pregnancy outcomes were observed. Results: (1) There were 16 AEH cases and 11 ECC cases among 27 recurrent patients who chose fertility-preserving therapy again. After re-treatment, CR was found in 13 out of 16 cases of AEH and 9 out of 11 cases of EEC. The overall CR rate was 81% (22/27). (2) After CR of recurrence, 5 cases (23%, 5/22) of re-recurrence were found after with a median time of 33 months (range 21-80 months). There were 4 cases underwent comprehensive surgical staging, and 1 patient chose the third round of fertility preservation therapy with fully informed consent, and CR was reached after 15 months. (3) There were 16 cases with pregnancy intention, with a total of 12 pregnancies, including 5 cases were natural pregnancy and 7 cases were assisted reproductive technology pregnancy. There were 5 live births. The follow-up time was up to May 2019, and the median follow-up time was 73 months (range 0-123 months). All 27 patients had disease free survival. Conclusions: Recurrent patients with AEH and EEC after achieving successful fertility-preserving therapy could choose fertility-preserving therapy again with comprehensive assessment and fully informed consent. After re-treatment, there is a certain tumor CR rate and pregnancy rate, while the close follow-up is required during treatment.
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Affiliation(s)
- Y J He
- Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing 100044, China
| | - Y Q Wang
- Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing 100044, China
| | - H R Tang
- Department of Obstetrics and Gynecology, Peking University Shenzhen Hospital, Shenzhen 518036, China
| | - M He
- Department of Obstetrics and Gynecology, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Y Rao
- Department of Gynecological Oncology, Tianjin Central Hospital of Gynecology Obstetrics, Tianjin 300100, China
| | - R Zhou
- Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing 100044, China
| | - J L Wang
- Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing 100044, China
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Li L, Zhao S, Wang S, Rao Y. CO2 hydrate formation kinetics based on a chemical affinity model in the presence of GO and SDS. RSC Adv 2020; 10:12451-12459. [PMID: 35497591 PMCID: PMC9051314 DOI: 10.1039/c9ra10073c] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 02/26/2020] [Indexed: 11/21/2022] Open
Abstract
Hydrate generation promotion and kinetic models are key issues in the hydrate utilization technology. The formation kinetics of CO2 hydrates in a graphene oxide (GO) and sodium dodecyl sulfate (SDS) compounding accelerator system was studied experimentally, and the influences of different concentrations on the hydrate formation time and gas consumption were revealed. The results show that with the combination of GO and SDS, the formation rate of CO2 hydrates was accelerated, the induction time and generation time were shortened, and the gas consumption increased. The optimal compounding concentration was 0.005% GO and 0.2% SDS. Compared with the observations for pure water and a single 0.005% GO system, the hydrate formation time was shortened by 69.7% and 12.2%, respectively, and the gas consumption increased by 11.24% and 3.2%. A chemical affinity model of CO2 hydrate formation was established for this system. The effects of the GO and SDS compound ratio, temperature and pressure on the chemical affinity model parameters were studied from the model point of view. On using Matlab to program the model and compare it with the experimental results, very good agreement was achieved. Through research, the chemical affinity model can accurately predict the formation of hydrates in complex systems. Hydrate generation promotion and kinetic models are key issues in the hydrate utilization technology.![]()
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Affiliation(s)
- Lijun Li
- School of Petroleum Engineering
- Changzhou University
- China
| | - Shuhua Zhao
- School of Petroleum Engineering
- Changzhou University
- China
| | - Shuli Wang
- School of Petroleum Engineering
- Changzhou University
- China
| | - Yongchao Rao
- School of Petroleum Engineering
- Changzhou University
- China
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Liang B, Rao Y, Duan X. The electrical properties and modulation of g-C 3N 4/β-As and g-C 3N 4/β-Sb heterostructures: a first principles study. RSC Adv 2019; 9:38724-38729. [PMID: 35540229 PMCID: PMC9076001 DOI: 10.1039/c9ra06357a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/28/2019] [Indexed: 11/24/2022] Open
Abstract
The electronic properties of the g-C3N4/β-As and g-C3N4/β-Sb heterojunctions are investigated via density functional theory. We find that both heterostructures are indirect band gap semiconductors that, when applied to a photocatalytic device, will suffer from inefficient light emission. Fortunately, the band gap of the two junctions can be adjusted by external biaxial strain. As strain increases from compression to extensive, both compounds undergo a transition from metals, indirect semiconductors to direct semiconductors. Moreover, due to the charge transfer, each junction forms a large built-in electric field, which helps to prevent the recombination of electrons and holes. Our results are expected to widen the potential applications of these heterojunctions in nanodevices. The electronic properties of the g-C3N4/β-As and g-C3N4/β-Sb heterojunctions are investigated via density functional theory.![]()
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Affiliation(s)
- Bo Liang
- School, of Physical Science and Technology, Ningbo University 315211 China .,Laboratory of Clean Energy Storage and Conversion, Ningbo University Ningbo 315211 China
| | - Yongchao Rao
- School, of Physical Science and Technology, Ningbo University 315211 China
| | - Xiangmei Duan
- School, of Physical Science and Technology, Ningbo University 315211 China .,Laboratory of Clean Energy Storage and Conversion, Ningbo University Ningbo 315211 China
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Wang S, Ding B, Rao Y, Chen F. Study on the influence of coconut oil on flow pattern and pressure drop of two-phase swirl flow. RSC Adv 2019; 9:32644-32655. [PMID: 35529768 PMCID: PMC9073093 DOI: 10.1039/c9ra05369g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 10/03/2019] [Indexed: 11/29/2022] Open
Abstract
In view of the widespread existence of swirl flow in surfactant systems in oil drilling, gas gathering, and gathering pipelines, surfactants can affect interfacial tension and thus change the flow pattern. In order to further study and master the swirl flow characteristics in surfactant systems, this experimental investigation was presented, focused on gas–liquid flow during swirl flow, and aiming to evaluate the effect of surfactant in flow patterns. The experimental medium was air and water, the swirler was a vane and the surfactant was natural coconut oil. The purity of coconut oil was 99.9%, and the concentration was 100–900 ppm. The surface tension of the surfactant solution was measured using a surface tension meter to determine the concentration of the coconut oil solution at the minimum surface tension. By analyzing the flow characteristics of the gas–liquid interface with a high-resolution camera, the flow pattern of the gas–liquid two-phase swirl flow under the surfactant system was divided into the swirl linear flow, the swirl wave stratified flow, the swirl axial flow, and the swirl dispersed flow. Compared with the gas–liquid two-phase flow swirl flow pattern without surfactant, it was found that the swirl bubble flow and the swirl slug flow were not present, which was related to the stability of the gas–liquid interface weakened by the decrease of surface tension between the gas and liquid. The effects of flow pattern, gas content, vane parameters, surfactant concentration and flow rate on pressure drop were systematically investigated. Finally, based on the experimental data, we modified the pressure drop model of the gas–liquid two-phase swirl flow under the surfactant system with the vane as the spinner. The calculated value of the pressure drop model agrees well with the experimental data. This model can provide technical support for the safe operation of oil and gas pipelines. In view of the widespread existence of swirl flow in surfactant systems in oil drilling, gas gathering, and gathering pipelines, surfactants can affect interfacial tension and thus change the flow pattern.![]()
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Affiliation(s)
- Shuli Wang
- School of Petroleum Engineering, Changzhou University Jiangsu 213164 China
| | - Boyang Ding
- School of Petroleum Engineering, Changzhou University Jiangsu 213164 China
| | - Yongchao Rao
- School of Petroleum Engineering, Changzhou University Jiangsu 213164 China
| | - Feng Chen
- School of Petroleum Engineering, Changzhou University Jiangsu 213164 China
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Cai D, Rao Y, Zhan Y, Wang Q, Chen S. EngineeringBacillusfor efficient production of heterologous protein: current progress, challenge and prospect. J Appl Microbiol 2019; 126:1632-1642. [DOI: 10.1111/jam.14192] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/13/2018] [Accepted: 12/28/2018] [Indexed: 12/18/2022]
Affiliation(s)
- D. Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - Y. Rao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - Y. Zhan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - Q. Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - S. Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
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Qian X, Zhao H, Rao Y, Nan Y, Wang Z, Wang X, Lian Q, Li J. Abstract PR509. Anesth Analg 2016. [DOI: 10.1213/01.ane.0000492893.54552.a3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Xu X, Rao Y, Liu D, Zhao Y. PT020 Factors Influencing Sleeping and the Impact of Sleeping on Quality of Life Among Chinese Middle-Aged Adults in Chongqing, China. Glob Heart 2016. [DOI: 10.1016/j.gheart.2016.03.452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Xu X, Liu L, Rao Y, Guo L, Zhao Y. PM017 Malnutrition in Early Life and Self-Reported Appetite in Adulthood in Chongqing, China. Glob Heart 2016. [DOI: 10.1016/j.gheart.2016.03.253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Xu X, Zhu R, Xie W, Xiong W, Ran M, Rao Y, Sharma M, Shen X, Zhao Y. PS032 Attitude Toward Secondhand Smoke and Related Behaviors of Exposure to Secondhand Smoke Among Urban Community Female Non-Smokers in Chongqing, China. Glob Heart 2016. [DOI: 10.1016/j.gheart.2016.03.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Xu X, Zhu R, Xie W, Xiong W, Ran M, Rao Y, Sharma M, Shen X, Zhao Y. PS033 Secondhand Tobacco Smoke Exposure and Smoking-Related Knowledge Among Urban Community Female Non-Smokers in Chongqing, China. Glob Heart 2016. [DOI: 10.1016/j.gheart.2016.03.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Cai B, Wen J, Rao Y, Tsien C, Huang J, Green O, Mutic S, Yablonskiy D, Gach H. SU-D-207A-04: Use of Gradient Echo Plural Contrast Imaging (GEPCI) in MR-Guided Radiation Therapy: A Feasibility Study Targeting Brain Treatment. Med Phys 2016. [DOI: 10.1118/1.4955651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Speirs C, LaBrash J, Mutic S, Rao Y, Rehman S, Roach M, Michalski J, Perkins S. PO-0859: Quantifying and categorizing plan rejections as a part of the clinical process improvement. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)32109-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
OBJECTIVE To describe the quality of life (QOL) of the migrant population with pulmonary tuberculosis (PTB) in West China, and identify factors associated with QOL. METHODS A pilot investigation was conducted among 103 migrant individuals with PTB in Nanchong Region, Sichuan Province, China. The QOL and social support of the patients were investigated using a short version of the World Health Organization Quality of Life questionnaire and the Social Support Rating Scale, respectively. RESULTS The mean scores of the QOL of the migrant population were respectively 12.1, 12.9 and 11.7 for the physical, psychological and environmental domains; these were significantly lower than those of the general Chinese population. Non-parametric tests detected the significant effects of the following: 1) educational levels on all domains, including social relationship; 2) age on all domains, except psychological; 3) personal income on the physical and environmental domains; and 4) subjective support on all domains, except psychological. Multivariate logistic regression analyses confirmed that educational levels and subjective support were significantly associated with the global health status of the migrant population. CONCLUSIONS The QOL of patients with TB among the migrant population in West China was poor; education and subjective support were important influential factors.
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Affiliation(s)
- X-F Gao
- Department of Preventive Medicine, North Sichuan Medical College, Nanchong, Sichuan, China
| | - Y Rao
- Tuberculosis Dispensary, YiLong Center for Disease Control and Prevention, Nanchong, Sichuan, China
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Shareef S, Sridhar I, Dakshayani K, Rao Y, Santhamma B. Evaluation of the effects of tramadol and diclofenac alone and in combination on post-cesarean pain. ACTA ACUST UNITED AC 2014. [DOI: 10.5455/2319-2003.ijbcp20140610] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Rao Y, Ma D, Li H, Esthappan J, Chang A, Grigsby P. A Clinically Useful Watershed-based Method of Auto-segmenting Apparent Diffusion Coefficient (ADC) Maps of Cervical Cancer. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.1146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Sasikumar R, Rao Y. Development of hybrid clones for tetanus. N Biotechnol 2009. [DOI: 10.1016/j.nbt.2009.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Rao Y, Wang YL, Li H, Zhang W, Liu J. Effects of Pregnancy on the Solubility of Halogenated Volatile Anaesthetics in Rat Blood and Tissues. Anaesth Intensive Care 2008; 36:830-4. [PMID: 19115652 DOI: 10.1177/0310057x0803600612] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study was designed to evaluate the effects of pregnancy on the solubility of halogenated volatile anaesthetics in rat blood and tissues. Tissue samples from 10 pregnant and 10 non-pregnant adult female Sprague Dawley rats, including the heart, liver, kidney and brain, were obtained and made into respective homogenates. Blood/gas and tissue/gas partition coefficients for halothane, sevoflurane and isoflurane were determined by the method of two-stage headspace equilibration by gas chromatography with each of the homogenates. Values were analysed by t-test or one-way analysis of variance. The solubility within blood and brain for halothane in the pregnant group (2.90 ± 0.44, 5.55 ± 0.73) was significantly lower than that of the non-pregnant group (3.42±0.23, 6.33±0.64; P <0.05). However, there were no significant differences between the two groups for liver, kidney or heart solubility. For sevoflurane and isoflurane, there were no significant differences in solubility between the two groups. In conclusion, pregnancy decreased the solubility of halothane within the blood and brain, whereas the solubility of halothane in other tissues including the liver, kidney and heart showed no significant alteration. Pregnancy did not affect the solubility of sevoflurane or isoflurane within blood or the other tissues studied.
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Affiliation(s)
- Y. Rao
- Department of Anesthesiology, Zhongnan Hospital, Wuhan University, Hubei, PR China
| | - Y.-L. Wang
- Department of Anesthesiology, Zhongnan Hospital, Wuhan University, Hubei, PR China
| | - H. Li
- Department of Anesthesiology, Zhongnan Hospital, Wuhan University, Hubei, PR China
| | - W. Zhang
- Department of Anesthesiology, Zhongnan Hospital, Wuhan University, Hubei, PR China
| | - J. Liu
- Department of Anesthesiology, Zhongnan Hospital, Wuhan University, Hubei, PR China
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Narsaiah A, Reddy A, Rao Y, Kumar E, Prakasham R, Reddy B, Yadav J. Magnesium-Cadmium Chloride,
a Bimetallic Catalyst System for the Allylation of Aldehydes
with Allyl Bromide: An Efficient Protocol for the Synthesis
of Homoallylic Alcohols. SYNTHESIS-STUTTGART 2008. [DOI: 10.1055/s-0028-1093170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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33
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Zhou M, Lei M, Rao Y, Nie Q, Zeng H, Xia M, Liang F, Zhang D, Zhang X. Polymorphisms of Vasoactive Intestinal Peptide Receptor-1 Gene and Their Genetic Effects on Broodiness in Chickens. Poult Sci 2008; 87:893-903. [PMID: 18420979 DOI: 10.3382/ps.2007-00495] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- M Zhou
- Department of Animal Genetics, Breeding and Reproduction, College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China
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Ke JJ, Zhan J, Feng XB, Wu Y, Rao Y, Wang YL. A comparison of the effect of total intravenous anaesthesia with propofol and remifentanil and inhalational anaesthesia with isoflurane on the release of pro- and anti-inflammatory cytokines in patients undergoing open cholecystectomy. Anaesth Intensive Care 2008; 36:74-8. [PMID: 18326136 DOI: 10.1177/0310057x0803600113] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The aim of the study was to investigate the effects of two anaesthetic techniques (total intravenous technique vs. inhalational technique) on changes in pro- and anti-inflammatory cytokine levels during open cholecystectomy. Forty ASA PS I-II patients undergoing open cholecystectomy were randomly assigned to two groups. Group R received total intravenous anaesthesia with propofol and remifentanil and group F received balanced inhalational anaesthesia with isoflurane. The plasma levels of tumour necrosis factor-alpha (TNF-alpha), interleukin IL-6 and interleukin IL-10 were measured during and after surgery. The pro-inflammatory cytokine levels (TNF-alpha and IL-6) and the anti-inflammatory cytokine (IL-10) showed a significant increase in their concentrations compared with pre-induction levels in both groups (P < 0.05). By the end of anaesthesia and surgery, TNF-alpha and IL-6 were significantly lower in group R than in group F (P < 0.05). At the end of anaesthesia and 12 hours postoperatively, IL-10 levels in group R were higher than in group F (P < 0.05). These findings suggest that total intravenous anaesthesia using propofol and remifentanil suppresses the inflammatory response caused by surgery to a greater extent than a balanced inhalation technique using isoflurane.
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Affiliation(s)
- J J Ke
- Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Hubei Province, Peoples Republic of China
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Yadav J, Rao Y, Reddy A, Narsaiah A, Subba Reddy B. Phosphomolybdic Acid Supported on Silica Gel as Mild, Efficient and Cost-Effective Catalyst for Chemoselective Protection of Amines with di-tert-Butyl Dicarbonate. LETT ORG CHEM 2008. [DOI: 10.2174/157017808783743957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Reddy C, Rao Y, Kumar T, Reddy K, Chandrasekhar S. Hydroxylamine Derivatives as Nucleophiles in Ferrier Glycosylation: Synthesis of Aminoxy Pseudoglycals. SYNTHESIS-STUTTGART 2008. [DOI: 10.1055/s-2007-1000828] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Yadav J, Reddy A, Rao Y, Narsaiah A, Reddy B. Samarium(III) Triflate Catalyzed Conjugate Addition of Amines to Electron-Deficient Alkenes. SYNTHESIS-STUTTGART 2007. [DOI: 10.1055/s-2007-990876] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Werbowetski-Ogilvie TE, Seyed Sadr M, Jabado N, Angers-Loustau A, Agar NYR, Wu J, Bjerkvig R, Antel JP, Faury D, Rao Y, Del Maestro RF. Inhibition of medulloblastoma cell invasion by Slit. Oncogene 2006; 25:5103-12. [PMID: 16636676 PMCID: PMC2072874 DOI: 10.1038/sj.onc.1209524] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 01/27/2006] [Accepted: 02/22/2006] [Indexed: 11/09/2022]
Abstract
Invasion of brain tumor cells has made primary malignant brain neoplasms among the most recalcitrant to therapeutic strategies. We tested whether the secreted protein Slit2, which guides the projection of axons and developing neurons, could modulate brain tumor cell invasion. Slit2 inhibited the invasion of medulloblastoma cells in a variety of in vitro models. The effect of Slit2 was inhibited by the Robo ectodomain. Time-lapse videomicroscopy indicated that Slit2 reduced medulloblastoma invasion rate without affecting cell direction or proliferation. Both medulloblastoma and glioma tumors express Robo1 and Slit2, but only medulloblastoma invasion is inhibited by recombinant Slit2 protein. Downregulation of activated Cdc42 may contribute to this differential response. Our findings reinforce the concept that neurodevelopmental cues such as Slit2 may provide insights into brain tumor invasion.
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Affiliation(s)
- T E Werbowetski-Ogilvie
- Brain Tumour Research Centre, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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Vaidya RA, Vaidya ADB, Patwardhan B, Tillu G, Rao Y. Ayurvedic pharmacoepidemiology: a proposed new discipline. J Assoc Physicians India 2003; 51:528. [PMID: 12974443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
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Wong K, Ren XR, Huang YZ, Xie Y, Liu G, Saito H, Tang H, Wen L, Brady-Kalnay SM, Mei L, Wu JY, Xiong WC, Rao Y. Signal transduction in neuronal migration: roles of GTPase activating proteins and the small GTPase Cdc42 in the Slit-Robo pathway. Cell 2001; 107:209-21. [PMID: 11672528 DOI: 10.1016/s0092-8674(01)00530-x] [Citation(s) in RCA: 431] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Slit protein guides neuronal and leukocyte migration through the transmembrane receptor Roundabout (Robo). We report here that the intracellular domain of Robo interacts with a novel family of Rho GTPase activating proteins (GAPs). Two of the Slit-Robo GAPs (srGAPs) are expressed in regions responsive to Slit. Slit increased srGAP1-Robo1 interaction and inactivated Cdc42. A dominant negative srGAP1 blocked Slit inactivation of Cdc42 and Slit repulsion of migratory cells from the anterior subventricular zone (SVZa) of the forebrain. A constitutively active Cdc42 blocked the repulsive effect of Slit. These results have demonstrated important roles for GAPs and Cdc42 in neuronal migration. We propose a signal transduction pathway from the extracellular guidance cue to intracellular actin polymerization.
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Affiliation(s)
- K Wong
- Department of Anatomy and Neurobiology, Washington University School of Medicine, 660 South Euclid Avenue, Saint Louis, MO 63110, USA
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Abstract
A new study demonstrating a pathway for neuronal migration in humans, but not in monkeys, suggests that migration has a key role in the evolution of the brain, as well as its development.
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Abstract
Phosphatidylinositol 3-kinase (PI3-K) has been shown to mediate insulin and insulin-like growth factor-1 (IGF-1)-induced nitric oxide (NO) generation and, thus, vascular tone. A role for PI3-K in G-protein-coupled receptor signal transduction has been reported. As beta (beta2)-adrenergic vascular actions are partly dependent on NO, we have investigated the role of PI3-K in isoproterenol (Iso) and IGF-1 induced endothelial NO synthase (ecNOS) activity in rat aortic endothelial cells (RAEC). Cell lysates of RAEC, exposed to Iso (10 micromol/L) for 5 min and 6 h, and to IGF-1 (100 nM) for 10 min and 6 h, or pretreated with PI3-K inhibitor Wortmannin (WT), were used for measuring PI3-K activity, p85kDa regulatory protein, and citrulline production. Results show that Iso and IGF-1 increased a p85 subunit and citrulline production, and also enhanced 32P incorporation into PIP3. Pretreatment with WT inhibited Iso-stimulated ecNOS, as well as, PI3-K activity. Iso enhanced association of ecNOS with the triton X-100-insoluble fraction of RAEC. These data indicate that the endothelial cell PI3-K pathway mediates, in part, the release of NO and subsequent vasorelaxation in response to this beta-agonist, as well as, IGF-1.
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Affiliation(s)
- E Isenović
- Department of Medicine, State University New York-Health Science Center, Brooklyn, New York, USA
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Wu JY, Feng L, Park HT, Havlioglu N, Wen L, Tang H, Bacon KB, Jiang Zh, Zhang Xc, Rao Y. The neuronal repellent Slit inhibits leukocyte chemotaxis induced by chemotactic factors. Nature 2001; 410:948-52. [PMID: 11309622 PMCID: PMC2072862 DOI: 10.1038/35073616] [Citation(s) in RCA: 333] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Migration is a basic feature of many cell types in a wide range of species. Since the 1800s, cell migration has been proposed to occur in the nervous and immune systems, and distinct molecular cues for mammalian neurons and leukocytes have been identified. Here we report that Slit, a secreted protein previously known for its role of repulsion in axon guidance and neuronal migration, can also inhibit leukocyte chemotaxis induced by chemotactic factors. Slit inhibition of the chemokine-induced chemotaxis can be reconstituted by the co-expression of a chemokine receptor containing seven transmembrane domains and Roundabout (Robo), a Slit receptor containing a single transmembrane domain. Thus, there is a functional interaction between single and seven transmembrane receptors. Our results reveal the activity of a neuronal guidance cue in regulating leukocyte migration and indicate that there may be a general conservation of guidance mechanisms underlying metazoan cell migration. In addition, we have uncovered an inhibitor of leukocyte chemotaxis, and propose a new therapeutic approach to treat diseases involving leukocyte migration and chemotactic factors.
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Affiliation(s)
- J Y Wu
- Department of Pediatrics, and Molecular Biology and Pharmacology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
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Hirata T, Fujisawa H, Wu JY, Rao Y. Short-range guidance of olfactory bulb axons is independent of repulsive factor slit. J Neurosci 2001; 21:2373-9. [PMID: 11264311 PMCID: PMC6762389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
During development, mitral cells, the major output neurons of the olfactory bulb, project their axons caudolaterally into the telencephalon and form the lateral olfactory tract (LOT). Two types of guidance cues have been suggested for this projection. First, a long-range factor Slit, which is secreted from the septum, repels mitral cell axons into a caudolateral direction. Second, the pathway of mitral cell axons contains a subset of neurons designated as lot cells, which guide the axons through short-range interactions. It is not clear how these two guidance cues relate to each other and how they share the physiological roles. Here we examined the behavior of mitral cell axons in organotypic culture on ectopic application of Slit and inhibition of endogenous Slit signaling. The results suggested that the short-range guidance cue in the LOT pathway functions independently from Slit. Furthermore, our results showed that removal of the septum and inhibition of Slit signaling did not affect the projection of mitral cell axons. Although the septum and exogenous Slit can repel olfactory bulb axons, our results cast doubts on the physiological relevance of the septum and endogenous Slit in guiding the projection of mitral cell axons.
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Affiliation(s)
- T Hirata
- Division of Brain Function, National Institute of Genetics, Mishima 411-8540, Japan.
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Chen JH, Wen L, Dupuis S, Wu JY, Rao Y. The N-terminal leucine-rich regions in Slit are sufficient to repel olfactory bulb axons and subventricular zone neurons. J Neurosci 2001; 21:1548-56. [PMID: 11222645 PMCID: PMC6762944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2000] [Revised: 11/06/2000] [Accepted: 11/14/2000] [Indexed: 02/19/2023] Open
Abstract
The Slit proteins are a new family of secreted guidance cues involved in axon guidance and neuronal migration. Each mammalian Slit protein contains >1400 amino acid residues, with four leucine-rich regions (LRRs), nine epidermal growth factor repeats, a laminin G domain, and a C-terminal cysteine-rich domain. A receptor for Slit is the transmembrane protein Roundabout (Robo), whose extracellular part contains five Ig domains and three fibronectin type III repeats. We report here that the LRRs in Slit are sufficient for binding to the Ig domains of Robo. Mutant forms of Slit containing only the LRRs function as chemorepellents for axons projecting from the olfactory bulb both in vitro and in the telencephalon. The LRRs can repel neurons migrating from the anterior subventricular zone (SVZa) to the olfactory bulb in brain slices isolated from neonatal rodents. However, the LRRs do not show repulsive effects on the SVZa neurons migrating in collagen gels. Our results indicate that the same LRRs are sufficient for guiding both axon projection and neuronal migration and suggest that the other regions in the Slit proteins may be involved in regulating the diffusion and distribution of the Slit proteins. The fact that the same domains are involved in guiding axon projection and neuronal migration further strengthens the idea of a conserved guidance mechanism for these important processes.
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Affiliation(s)
- J H Chen
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Rao Y, Xiao P, Xu S. Effects of intrahippocampal aniracetam treatment on Y-maze avoidance learning performance and behavioral long-term potentiation in dentate gyrus in rat. Neurosci Lett 2001; 298:183-6. [PMID: 11165437 DOI: 10.1016/s0304-3940(00)01744-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Effects of intrahippocampal treatment of aniracetam, a selective agonist for DL-alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproionic acid (AMPA) receptors, on Y-maze avoidance learning task and behavioral long-term potentiation (LTP) in perforant path-dentate gyrus were studied in freely moving rats by using in vivo electrophysiology combined with behavioral tests. The results were as follows: (1) intrahippocampal treatment of aniracetam reversibly enhanced basal synaptic transmission in perforant path to dentate gyrus in a dosage dependent manner; (2) aniracetam produced improvement in Y-maze learning performance when administration occurred 5 min prior to maze learning; (3) aniracetam administration significantly facilitated behavioral LTP in dentate gyrus, while the maximal amplitude of LTP has no significant difference when compared to saline group. The present results indicate that hippocampal AMPA receptors are involved in learning and memory.
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Affiliation(s)
- Y Rao
- Institute of Senile Encephalopathy, The Second School of Medicine, Guangzhou University of Traditional Chinese Medicine, 510405, PR, Guangzhou, China.
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