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241.
BackgroundAfter the elimination of leprosy in 1995, there were 10–30 newly detected leprosy cases every year in Zhejiang Province, and the epidemiological characteristics of the newly detected leprosy cases have changed. While most of the newly detected cases came from other provinces in China, not Zhejiang, it brought a new challenge for leprosy prevention and control in post- elimination era in Zhejiang, China. This study was aimed to understand the temporal-spatial distribution characteristics of newly detected leprosy cases, and provide the scientific rationales for the development of leprosy control strategy.MethodsData on the demographic of Zhejiang Province from 2011 to 2019 were obtained from the China Information System for Disease Control and Prevention, and the epidemiological data on leprosy cases newly detected in Zhejiang Province from 2011 to 2019 were obtained from the LEPROSY MANAGEMANT INFORMATION SYSTEM IN CHINA (LEPMIS), and temporal-spatial distributions were described. The geographic information system software—ArcGIS 10.4 was used to draw the statistical maps, and Geoda 1.14.0 was used for local spatial autocorrelation analysis (local Getis coefficient method). Ridley-Jopling classification was used to classify the clinical types into I, TT, BT, BB, BL or LL. Two-group classification system developed by the World Health Organization (WHO) was used and cases were classified into multibacillary (MB) type or paucibacillary (PB) type.ResultsA total of 167 leprosy cases were reported in Zhejiang Province during 2011–2019, including 107 cases in males and 60 in females. The mean age at diagnosis was 37.99±14.81 years, and 94.01% of the cases were detected through the examination at skin-clinics. The number of workers, MB cases, G2D cases were 81 (48.50%), 159 (94.01%), 24 (14.37%) respectively, and the rate of early detection increased from 45.16% in 2011 to 90.91% in 2019. Leprosy cases were reported in all the prefectures of Zhejiang except Zhoushan City. The cases in local population accounted for 23.35% (39 cases), and the cases in floating population (especially coming from high epidemic provinces in China) accounted for 76.65% (128 cases). The annual number of newly detected cases showed a decreasing trend, from 31 cases in 2011 to 11 in 2019. Time of the floating population living in Zhejiang Province ranged from several months to more than 10 years. The annual proportion of new cases with G2D declined from 22.58% in 2011 to 9.09% in 2019. The results of local indicators of autocorrelation (LISA) analysis showed that the high-high areas were mainly concentrated in the middle and northeast of Zhejiang Province, while the low-low areas were in the east and southwest.ConclusionA few scattered cases still can be seen in post-elimination era, and there was a spatial clustering of the newly detected leprosy cases in Zhejiang Province. Most of the cases in Zhejiang Province were from other high epidemic provinces in China, which brought a new challenge for leprosy control and prevention in post- elimination era in Zhejiang, and it is also necessary to strengthen the early detection and standard management of the leprosy cases in floating population in Zhejiang.  相似文献   
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Biomarkers for peptide/protein oxidation under oxidative stress (OS) hold both incredible application potential as well as significant challenges. In this article, liquid chromatography and mass spectrometry were applied to establish a new method for evaluating the oxidation site and degree of peptide oxidized, with its oxidative product serving as biomarker. In the three model peptides, peptide FMRF (containing a methionine) was prone to undergo oxygen addition under UV/H2O2 oxidization, forming a sulfoxide (FM(O)RF) with a stable chromatographic peak separate from the model peptides. The oxidation content of FMRF, expressed as SFM(O)RF/(SFM(O)RF + SFMRF), is positively correlated with oxidation time. Based on sequence analysis of FM(O)RF, the oxidation mechanism (site and extent) of FMRF under UV/H2O2 oxidization was explicitly clarified. By comparing the specific injury to each model peptide, we found that the oxidative products of Met‐containing peptides are good biomarkers for OS. This research not only expands the range of biomarkers for OS, but also provides an efficient and accurate method for evaluating oxidation damage to peptides and even proteins. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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The Arabidopsis thaliana histone H2A-1 is important for Agrobacterium tumefaciens–mediated plant transformation. Mutation of HTA1, the gene encoding histone H2A-1, results in decreased T-DNA integration into the genome of Arabidopsis roots, whereas overexpression of HTA1 increases transformation frequency. To understand the mechanism by which HTA1 enhances transformation, we investigated the effects of overexpression of numerous Arabidopsis histones on transformation and transgene expression. Transgenic Arabidopsis containing cDNAs encoding histone H2A (HTA), histone H4 (HFO), and histone H3-11 (HTR11) displayed increased transformation susceptibility, whereas histone H2B (HTB) and most histone H3 (HTR) cDNAs did not increase transformation. A parallel increase in transient gene expression was observed when histone HTA, HFO, or HTR11 overexpression constructs were cotransfected with double- or single-stranded forms of a gusA gene into tobacco (Nicotiana tabacum) protoplasts. However, these cDNAs did not increase expression of a previously integrated transgene. We identified the N-terminal 39 amino acids of H2A-1 as sufficient to increase transient transgene expression in plants. After transfection, transgene DNA accumulates more rapidly in the presence of HTA1 than with a control construction. Our results suggest that certain histones enhance transgene expression, protect incoming transgene DNA during the initial stages of transformation, and subsequently increase the efficiency of Agrobacterium-mediated transformation.  相似文献   
244.
Sodium‐dependent glucose cotransporters (SGLTs) play an important role in glucose reabsorption in the kidney and have been identified as promising targets to treat diabetes. Because of the side effects like glucose and galactose malabsorption by targeting SGLT1, highly selective SGLT2 inhibitors are more promising in the treatment of diabetes. To understand the mechanism of selectivity, we conducted selectivity‐based three‐dimensional quantitative structure–activity relationship studies to highlight the structure requirements for highly selective SGLT2 inhibitors. The best comparative molecular field analysis and comparative molecular similarity indices analysis models showed the noncross‐validated coefficient (r2) of 0.967 and 0.943, respectively. The predicted correlation coefficients (r2pred) of 0.974 and 0.938 validated the reliability and predictability of these models. Besides, homology models of SGLT2 and SGLT1 were also constructed to investigate the selective mechanism from structure‐based perspective. Molecular dynamics simulation and binding free energy calculation were performed on the systems of a potent and selective compound interacting with SGLT2 and SGLT1 to compare the different binding modes. The simulation results showed that the stretch of the methylthio group on Met241 had an essential effect on the different binding modes between SGLT1 and SGLT2, which was consistent with the three‐dimensional quantitative structure–activity relationship analysis. Hydrogen bond analysis and binding free energy calculation revealed that SGLT2 binding complex was more stable and favorable than SGLT1 complex, which was highly correlated with the experimental results. Our obtained results give useful information for the investigation of the inhibitors' selectivity between SGLT2 and SGLT1 and will help for further development of highly selective SGLT2 inhibitors. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Liang  Zhourui  Liu  Fuli  Wang  Wenjun  Zhang  Pengyan  Yuan  Yanmin  Liu  Yi  Yao  Haiqin  Jia  Rujie  Sun  Xiutao  Wang  Feijiu 《Journal of applied phycology》2022,34(2):1059-1072
Journal of Applied Phycology - Neopyropia katadae is one of the important economic seaweeds in China. A mass of free-living conchocelis is needed in the commercial cultivation of N. katadae. This...  相似文献   
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慢性心衰作为发病率和死亡率很高的一种疾病,其主要表现为心脏供血功能下降,无法满足身体需求。β 肾上腺素受体信号通路对 于维持心脏正常生理功能有重要意义,心衰时,β 肾上腺素受体信号通路也发生很大改变。基于对 β 肾上腺素受体信号通路的机制研究, 目前 β1 肾上腺素受体拮抗剂被广泛应用于心衰治疗,但 β2 肾上腺素受体的功能还有争议。综述 β2 肾上腺素受体在心衰过程中作用的研究 进展,提出 β2 肾上腺素受体激动剂联合 β1 肾上腺素受体拮抗剂治疗心衰的策略,旨在为心衰治疗药物的开发提供参考。  相似文献   
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The purpose of this paper is to demonstrate that near‐infrared (NIR) spectroscopic imaging can provide spatial distribution (maps) of the absolute concentration of hemoglobin + myoglobin, oxygen saturation parameter and optical pathlength, reporting on the biochemico‐physiological status of a beating heart in vivo. The method is based on processing the NIR spectroscopic images employing a first‐derivative approach. Blood‐pressure‐controlled gating compensated the effect of heart motion on the imaging. All the maps are available simultaneously and noninvasively at a spatial resolution in the submillimeter range and can be obtained in a couple of minutes. The equipment has no mechanical contact with the tissue, thereby leaving the heart unaffected during the measurement. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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