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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang Wen-Bo He xiu-qin Hu peng-fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

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银纳米一维复式阵列表面等离激元光谱性质

光谱学与光谱分析 2024年第8期44卷 2137-2145页

作者：张钦秀王鹏飞张悦王婷王玮熊涛孙诚大连大学物理科学与技术学院辽宁大连116622 辽宁省光电信息技术工程实验室辽宁大连116622

纳米尺寸的贵金属在入射光的激发下能够产生表面等离激元效应,即光在金属表面与电子发生耦合,引起金属表面自由电子集体震荡的现象。当自由电子的震荡频率与入射光的频率相同时,可以引起等离激元共振,产生独特的光谱特性。贵金属纳米颗... 详细信息

纳米尺寸的贵金属在入射光的激发下能够产生表面等离激元效应,即光在金属表面与电子发生耦合,引起金属表面自由电子集体震荡的现象。当自由电子的震荡频率与入射光的频率相同时,可以引起等离激元共振,产生独特的光谱特性。贵金属纳米颗粒的等离激元共振效应在物理、化学、生物等各个领域具有广泛应用。基于银纳米颗粒,提出一种一维复式阵列结构,利用时域有限差分方法研究该贵金属阵列的表面等离激元性质。在该结构中,以SiO_(2)为基底,两种不同的银纳米颗粒沿y轴方向放置在SiO_(2)基底的表面上,形成一维复式阵列,平面波入射光沿z轴负方向垂直入射。实验观察到,在300~1200 nm的波长范围内,该复式阵列结构的表面等离激元能够被有效激发,在其吸收光谱上有两个等离激元共振峰。通过调节该结构纳米颗粒的尺寸、形状和阵列周期等结构参数,等离激元共振峰和电磁场模式均发生有规律的变化。此外,固定其中一个银纳米颗粒不变,改变另一颗粒尺寸,可以发现其吸收曲线的两个共振峰发生不同的变化,结合电场图可以得出两个峰所对应的等离激元共振具有不同的电磁场模式。通过改变其中一个银纳米颗粒的形状,如四棱锥、球体、圆柱体和正方体,可以发现当颗粒形状发生变化时,两个共振峰对应的波长均不发生变化,但是不同颗粒形状所产生的电场分布明显不同,底面处的相对电场强度差别也很明显,依此同样可以验证其吸收曲线存在两个不同电磁场模式的共振峰。研究结果对基于贵金属纳米颗粒阵列结构表面等离激元器件的设计研究工作具有一定意义。

关键词：表面等离激元贵金属时域有限差分

Riboflavin concentration in corneal stroma after intracameral injection

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International Journal of Ophthalmology(English edition) 2015年第3期8卷 470-475页

作者： Na Li xiu-Jun peng zheng-Jun Fan Xu pang Yu Xia Teng-fei Wu Chinese PLA Medical School & Chinese PLA General Hospital Department of Ophthalmology Navy General Hospital of Chinese PLA

AIM: To evaluate the enrichment of riboflavin in the corneal stroma after intracameral injection to research the barrier ability of the corneal endothelium to riboflavin in ***: The right eyes of 30 New Zealand white rabbits were divided into three groups. Different concentrations riboflavin-balanced salt solutions(BSS)were injected into the anterior chamber(10 with 0.5%, 10 with 1%, and 10 with 2%). Eight corneal buttons of 8.5mm in diameter from each group were dissected at 30 min after injection and the riboflavin concentrations in the corneal stroma were determined using high-performance liquid chromatography(HPLC) after removing the epithelium and endothelium. The other two rabbits in every group were observed for 24 h and sacrificed. As a comparison, the riboflavin concentrations from 16 corneal stromal samples were determined using HPLC after instillation of 0.1% riboflavin-BSS solution for30 min on the corneal surface(8 without epithelium and 8with intact epithelium).RESULTS: The mean riboflavin concentrations were11.19, 18.97, 25.08, 20.18, and 1.13 μg/g for 0.5%, 1%, 2%,de-epithelialzed samples, and the transepithelial groups,respectively. The color change of the corneal stroma and the HPLC results showed that enrichment with riboflavin similar to classical de-epithelialized corneal collagen crosslinking(CXL) could be achieved by intracameral 1%riboflavin-BSS solution after 30min; the effect appeared to be continuous for at least 30 ***: Riboflavin can effectively penetrate the corneal stroma through the endothelium after an intracameral injection in vivo, so it could be an enhancing method that could improve the corneal riboflavin concentration in transepithelial CXL.

关键词： riboflavin cornea intracameral injection high-performance liquid chromatography endothelium

Discovery of a Homolog of Siderophilin in a Plant

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Journal of Integrative Plant Biology 2005年第12期47卷 1409-1411页

作者： Yun-Biao fei peng-xiu CAO Su-qin GAO Ling-Bo WEI Bin WANG Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China

Members belonging to the siderophilin family are iron-binding and iron-transporting proteins, which includes transferrin and lactoferrin. They have only been found in animals previously. If siderophilin could be found in and isolated from a plant, its production and subsequent extensive application could be increased. The present study is the first to report the discovery of a homolog of siderophilin in a plant. In order to purify antifreeze proteins from Ammopiptanthus mongolicus （Maxim.） Cheng f., the authors processed the proteins from the leaves using techniques such as column chromatography using DEAE-Cellulose-52, gel filtration via Sephacryl S-100 HR medium, hydrophobic interaction chromatography, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Mass spectroscopy was performed on the three proteins purified and the sequence of one of the proteins （containing 32 amino acids） was found to have 97% homology with the corresponding part of one type of human lactoferrin. Moreover, one of the two peptides belongs to an iron-binding domain. So, it is possible that siderophilin also exists in plants and plays a role as an antibacterial and antifungal, among other actions.

关键词： antibacterial iron-binding domain lactoferrin siderophilin transferrin.

基于16S rDNA高通量测序技术研究金银花和黄芩及其配伍对急性肺炎小鼠肠道菌群的影响

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动物医学进展 2024年第8期45卷 45-52页

作者：马涛纪鹏魏彦明王秀琴华永丽马挺杨昊赤李琛琛张文飞甘肃农业大学动物医学院甘肃兰州730070 宁夏农林科学院动物科学研究所宁夏银川750002

研究金银花、黄芩、金银花-黄芩1:1配伍对脂多糖(LPS)诱导急性肺炎小鼠肠道菌群的影响。制备金银花、黄芩及其配伍的水煎液,选用90只SPF级雄性昆明小鼠,随机分为6组(对照组、模型组、地塞米松组、金银花组、黄芩组、金银花-黄芩1:1配伍... 详细信息

研究金银花、黄芩、金银花-黄芩1:1配伍对脂多糖(LPS)诱导急性肺炎小鼠肠道菌群的影响。制备金银花、黄芩及其配伍的水煎液,选用90只SPF级雄性昆明小鼠,随机分为6组(对照组、模型组、地塞米松组、金银花组、黄芩组、金银花-黄芩1:1配伍组),每组15只,连续灌服相应药物7d,正常对照组和模型组灌服等量生理盐水。结果显示,模型组与对照组小鼠肠道菌群差异显著,金银花、黄芩、金银花-黄芩1:1配伍组和地塞米松组介于对照组和模型组之间;与模型组相比,各给药组小鼠肠道菌群的分离程度及群落结构和组成均有显著差异;模型组梭菌纲等有益菌的丰度降低,拟杆菌纲等条件致病菌的丰度升高。组间比较发现,与对照组相比,模型组帕拉普氏菌属(Paraprevotella)、考拉杆菌属(Phascolarctobacterium)等相对丰度增加;与模型组相比,金银花组和金银花-黄芩1:1配伍组巨单胞菌属(Megamonas)相对丰度增加,黄芩组柯林斯菌属(Collinsella)相对丰度增加。模型组主要影响细胞外基质(ECM)受体相互作用等代谢通路;各给药组主要影响蛋白酶体和氨基酸代谢通路。证实金银花、黄芩及其配伍可通过调节肠道菌群稳态来抵抗LPS诱发的急性肺炎,其中金银花-黄芩1:1配伍改善肠道菌群紊乱的效果更明显。

关键词：金银花黄芩配伍急性肺炎肠道菌群

Elevated soluble 4-1BB is associated with serum markers of hepatitis B virus in patients with chronic hepatitis B

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World Journal of Clinical Cases 2021年第7期9卷 1619-1630页

作者： Meng-Ru Zhan xiu-Zhu Gao Chang Wang fei peng Xiao-Mei Wang Hong-qin Xu Jun-Qi Niu Department of Hepatology The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Phase I Clinical Research Center The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

BACKGROUND Previous studies have suggested that the costimulatory molecule 4-1BB plays pivotal roles in regulating immunity during chronic viral ***,up to now,there are few studies about 4-1BB in chronic hepatitis B(CHB).AIM To clarify this issue,we report our comprehensive study results on the expression levels of 4-1BB in patients with *** From September 2018 to June 2019,a total of 64 patients with CHB were recruited from the Department of Hepatology,The First Hospital of Jilin *** blood samples were collected from 52 treatment-naïve and 12 entecavir-treated patients with CHB as well as 37 healthy donors(including 24 healthy adults and 13 healthy children).The levels of soluble 4-1BB(s4-1BB)in plasma were measured by ELISA.4-1BB mRNA expression in peripheral blood mononuclear cells was detected by real-time quantitative *** The s4-1BB levels in the plasma of patients with CHB were significantly higher than those in healthy adults(94.390±7.393 ng/mL vs 8.875±0.914 ng/mL,P<0.001).In addition,the s4-1BB level in plasma was significantly increased in patients with a higher viral load and a disease flare ***,there were no significant differences between treatment-naïve and entecavir-treated ***,among treatment-naïve patients with CHB,the levels of s4-1BB in plasma had a significant positive correlation with hepatitis B surface antigen,hepatitis B virus DNA,hepatitis B e antigen,and triglyceride levels(r=0.748,P<0.001;r=0.406,P=0.004;r=0.356,P=0.019 and r=-0.469,P=0.007,respectively).The 4-1BB mRNA expression was higher in the peripheral blood mononuclear cells of patients with CHB than in the peripheral blood mononuclear cells of healthy adults,but the difference was not statistically *** These results suggest that the levels of s4-1BB may be associated with pathogenesis of hepatitis B virus and therefore may be a promising biomarker for disease progression.

关键词： Hepatitis B virus Hepatitis B Chronic 4-1BB Soluble 4-1BB Hepatitis B virus serum marker

Application of remimazolam transversus abdominis plane block in gastrointestinal tumor surgery

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World Journal of Gastrointestinal Oncology 2023年第12期15卷 2101-2110页

作者： Jun Liu Jian-Min Tian Guo-Ze Liu Jun-Na Sun peng-fei Gao Yong-Qiang Zhang xiu-qin Yue Department of Anesthesiology and Perioperative Medicine The First Affiliated Hospital of Xinxiang Medical UniversityWeihui 453100Henan ProvinceChina

BACKGROUND Transversus abdominis plane block(TAPB)is a block of the abdominal afferent nerve fibers between the internal oblique muscle and the transverse abdominal muscle achieved with local *** can effectively block the conduction of the anterior nerve of the abdominal wall and exert a good analgesic ***,the effect of combining the block with remimazolam on anesthesia in patients undergoing gastrointestinal tumor surgery is still *** To examine the effects of combining TAPB with remimazolam on the stress response and postoperative recovery of gastrointestinal tumor surgery *** A retrospective analysis was conducted on the clinical data of 102 individuals diagnosed with gastrointestinal malignancies who underwent laparoscopic surgery under general anesthesia between April 2020 and June *** patients were categorized into a control group(n=51),receiving remimazolam for general anesthesia,and an observation group(n=51),receiving TAPB combined with remimazolam for general anesthesia.A comparison was made between both groups in terms of hemodynamic parameters,stress markers,pain levels,recovery quality,analgesic effects,and adverse reactions during the perioperative *** The observation group had significantly higher heart rates at time points 1 min after induction and upon leaving the operating room than the control group(P<0.05).The mean arterial pressure at time point T1 in the observation group was significantly higher than that in the control group(P<0.05).Five minutes after extubation,the levels of the hormones adrenaline and noradrenaline in the observation group were considerably lower than those in the control group(P<0.05).At 12 h,24 h,and 48 h following surgery,the visual analog scale scores of the observation group were considerably lower than those of the control group(P<0.05).The observation group had shorter awakening and extubation times and lower Riker sedation-agitation scale scores than the con

关键词： Transversus abdominis plane block Remimazolam General anesthesia Gastrointestinal tumor surgery Stress response

Differential analysis of lymph node metastasis in histological mixed-type early gastric carcinoma in the mucosa and submucosa

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World Journal of Gastroenterology 2018年第1期24卷 87-95页

作者： Qian Zhong Qi Sun Gui-fang Xu xiu-qin Fan Yuan-Yuan Xu fei Liu Shi-Yi Song Chun-Yan peng Lei Wang Department of Gastroenterology the Affiliated Drum Tower Hospital of Nanjing University Medical School Department of Pathology the Affiliated Drum Tower Hospital of Nanjing University Medical School

AIM To investigate the relationship between histological mixed-type of early gastric cancer(EGC) in the mucosa and submucosa and lymph node metastasis(LNM).METHODS This study included 298 patients who underwent gastrectomy for EGC between 2005 and 2012. Enrolled lesions were divided into groups of pure differentiated(pure D), pure undifferentiated(pure U), and mixed-type according to the proportion of the differentiated and undifferentiated components observed under a microscope. We reviewed the clinicopathological features, including age, sex, location, size, gross type, lymphovascular invasion, ulceration, and LNM, among the three groups. furthermore, we evaluated the predictors of LNM in the mucosa-confined *** Of the 298 patients, 165(55.4%) had mucosa-confined EGC and 133(44.6%) had submucosa-invasive EGC. Only 13(7.9%) cases of mucosa-confined EGC and 30(22.6%) cases of submucosa-invasive EGC were observed to have LNM. The submucosal invasion(OR = 4.58, 95%CI: 1.23-16.97, P = 0.023), pure U type(OR = 4.97, 95%CI: 1.21-20.39, P = 0.026), and mixedtype(OR = 5.84, 95%CI: 1.05-32.61, P = 0.044) were independent risk factors for LNM in EGC. The rate of LNM in mucosa-confined EGC was higher in the mixedtype group(P = 0.012) and pure U group(P = 0.010) than in the pure D group, but no significant difference was found between the mixed-type group and pure U group(P = 0.739). Similarly, the rate of LNM in the submucosa-invasive EGC was higher in the mixedtype(P = 0.012) and pure U group(P = 0.009) than in the pure D group but was not significantly different between the mixed-type and pure U group(P = 0.375). Multivariate logistic analysis showed that only female sex(OR = 5.83, 95%CI: 1.64-20.70, P = 0.028) and presence of lymphovascular invasion(OR = 13.18, 95%CI: 1.39-125.30, P = 0.020) were independent risk factors for LNM in mucosa-confined EGC, while histological type was not an independent risk factor for LNM in mucosa-confined EGC(P = 0.106).CONCLUSION fo

关键词： early gastric carcinoma mixed-type lymph node metastasis mucosa lymphovascular invasion

Photoredox-Catalyzed Hydrocarboxymethylation of Alkenes

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CCS Chemistry 2021年第10期3卷 95-104页

作者： Jie Fang Qiang Hu Wan-Li Dong Guo-Qiang Xu xiu-qin Hu Yong-Chun Luo peng-fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000 Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang 330096

Direct introduction of a carboxyl group into molecules is one of the most useful methods for the preparation of carboxylic acids,which avoids the conversion of various preexisting functional groups and features good step-and ***,the methods for the direct synthesis of two-carbon added carboxylic acids from the precursors remain ***,we first report a general and mild method for the direct synthesis of a range of aliphatic acids by photoredox-catalyzed hydrocarboxymethylation of alkenes with good toleration of various functional groups in which bromoacetic acid is utilized as an ideal two-carbon synthon.

关键词： photoredox catalysis unactivated alkenes bromoacetic acid two-carbonsynthon fatty acids