Terahertz Time-Domain Spectroscopy of Four Hydroxycinnamic Acid Derivatives

The well-resolved absorption spectra of the hydroxycinnamic acid (HCA) derivatives, caffeic acid, ferulic acid, sinapic acid and chlorogenic acid, were measured over the frequency region from 0.3 to 2.0 THz at 294 K with terahertz time-domain spectroscopy (THz-TDS). Theoretical calculation was applied to assist the analysis and assignment of the individual THz absorption spectra of the HCA derivatives with density functional theory (DFT). The distinctive spectral features were originated from the collective motion of molecules held together by hydrogen bonds. The real and imaginary parts of dielectric function of the four HCA derivatives were also obtained.     

Light-induced Difference Terahertz Spectroscopy

Visible/near-infraredlaser-induced difference spectroscopy basedon a time-domain terahertz system has beendeveloped, and used to study copperpathancyonine. We find that the absorptionpeak of this molecule at 1.08 THz changessignificantly under 790 nm laserexcitation, suggesting that we haveobserved the first evidence of vibrationalmode changes in the THz range induced byvisible/near-infrared light.     

Terahertz Pulse Spectroscopy of Biological Materials: L-Glutamic Acid

We report the terahertzpulse spectra of L-glutamic acid. Thereare a number of well-resolved transitionsin the 1.75–2.5 THz (58–83 cm^-1)region. These are compared with publishedtheoretical data on intra andintermolecular transitions. We could notfind any correlation with the theoreticalvalues. However, it was noted that thetheoretical model did not include anycrystalline or hydrogen-bonding effects.     

褪黑素的太赫兹时域光谱

太赫兹时域光谱技术是一种新兴的无损探测技术。利用太赫兹波的低能性以及大部分生物分子的振动跃迁和旋转在该频段表现出的强色散和吸收作用等特点,可以对生物分子及生命体的活动进行无损探测和研究。本文分别采用透射式和反射式太赫兹时域光谱系统,对不同质量比的褪黑素压片进行测试,分析它在太赫兹波段的光学性质,发现它在0.29、0.50、0.70、0.91、1.20、2.17和2.55 THz处存在特征吸收峰;频域谱的强度随样品浓度的变化呈线性关系。利用Gaussian 09及Gaussian VIEW软件进行模拟分析,得到褪黑素在0.46、0.91、1.15、2.01、2.23和2.61 THz处存在特征吸收峰,为实验结果提供了有力地支持。这些工作为褪黑素等生化样品的检测和鉴定提供了依据和参考。     

血尿酸水平与冠状动脉病变程度的关系探讨

目的:探讨血尿酸(SUA)水平与冠状动脉病变程度的关系。方法:将268例疑似冠心病(CHD)患者,经冠状动脉造影分为冠心病组198例和非冠心病组70例;冠心病组又分为单支病变组80例,双支病变组56例,三支病变组62例。分别检测各组研究对象血尿酸含量,同时记录年龄、性别、吸烟、高血压、糖尿病、血尿酸及冠状动脉造影结果,分析血尿酸与已知冠心病主要危险因素、冠状动脉病变程度的相关性。结果:冠心病组血尿酸水平(395.35±84.40)μmol/L,显著高于非冠心病组(282.20±66.68)μmol/L(P<0.05)。单支病变组(338.48±77.36)μmol/L、双支病变组(399.62±84.36)μmol/L、三支病变组(445.16±92.20)μmol/L,血尿酸水平呈递增趋势,各组之间的差异有统计学意义。结论:血尿酸水平可反映冠状动脉病变严重程度。降尿酸治疗有望成为心血管疾病防治的一种新途径。     

Uric Acid Metabolism in Patients with Primary Gout and the Metabolic Syndrome

Forty-four patients (40 males) with a mean age of 58 years were included in this pilot study. Mean serum urate concentration in patients with and without the metabolic syndrome (MS) was 8.8 mg/dL and 8.1 mg/dL, respectively. Urinary uric acid excretion was 543 mg/day/1.73m² in the former and 609 mg/day/1.73m² in the latter. Uric acid to creatinine ratio was 0.37 mg/mg in patients with the MS and 0.42 mg/mg in those without the MS. Mean serum urate increased from 8.6 mg/dL in subjects with three or more MS components to 10.3 mg/dL in those with five MS components. Serum urate was markedly lower in patients with mild MS (9 patients, 8.6 mg/dL) as compared to severe MS (10 patients, 9.2 mg/dL). In contrast, urinary uric acid to creatinine ratio was 0.42 mg/mg in patients with gout and mild MS and 0.33 mg/mg in gout patients with severe MS. Uric acid underexcretion appears to be more severe in gout patients with the MS. This disturbance appears to be related to the severity of the MS.     

脑血管疾病患者血尿酸和纤维蛋白原的测定与分析

目的:为了解脑血管疾病患者血尿酸、血浆纤维蛋白原水平及相互关系。方法:对81例脑梗死患者、77例脑出血患者和55例时照者采血测定血尿酸、血浆纤维蛋白原,并分析二者的相关性。结果:脑梗死疾病组和脑出血疾病组UA和Fib水平均高于时照组(P＜0．05);脑血管疾病组组间无差异(P□0．05);血尿酸和血浆纤维蛋白原二者间无相关性。结论:血尿酸、血浆纤维蛋白原作为脑血管疾病的危险因素可能是独立存在的。     

Effects of Losartan/Hydrochlorothiazide on Serum Uric Acid Levels and Blood Pressure in Hypertensive Patients

The effect of a mixed formulation of 50 mg losartan (LOS) and 12.5 mg hydrochlorothiazide (HCTZ) on blood pressure and the uric acid metabolism was analyzed in 73 patients who switched to this formulation from other antihypertensive drugs. Eight patients who switched to the formulation from the regular dose of renin-angiotensin (RA) inhibitor (angiotensin receptor blocker [ARB] or angiotensin-converting enzyme [ACE] inhibitor) only showed a significant decrease in blood pressure, from 156.9 ± 14.1/88.6 ± 9.7 mmHg to 128.3 ± 16.0/76.1 ±10.7 mmHg (p = 0.007), and a significant increase in serum uric acid levels, from 5.2 ± 1.1 mg/dL to 6.8 ± 0.7 mg/dL (p = 0.02). In the other 50 patients who switched from a combination of the regular dose of RA inhibitor and calcium channel blocker (CCB), their blood pressure significantly increased, from 126.0 ± 13.8/72.0 ± 10.0 mmHg to 132.5 ± 16.4/76.5 ± 11.3 mmHg (p = 0.02), and their serum uric acid levels also significantly increased, from 5.6 ± 1.1 mg/dL to 6.1 ± 1.3 mg/dL (p = 0.0002). Considering that guidelines recommend using antihypertensive therapies that do not lead to an increase in serum uric acid levels, we conclude that using the ARB/HCTZ combination is less suitable than the regular dose of the ARB/CCB combination due to its effect on hypertension and serum uric acid levels.     

尿酸代谢失衡与心血管疾病及药物干预

尿酸是体内嘌呤代谢的终末产物,与各类心血管疾病的发生发展密切相关,是心血管疾病的重要危险因子之一。综述尿酸的代谢及生理病理意义,尿酸代谢失衡与急性心肌梗死、高血压、胰岛素抵抗、肥胖症等心血管疾病的关联以及尿酸代谢失衡的药物干预与心血管保护作用。     

SGLT2抑制剂对2型糖尿病患者血糖、血尿酸水平及心脏功能的影响

摘要 目的：研究SGLT2抑制剂对2型糖尿病患者血糖、血尿酸水平及心脏功能的影响。方法：选取我院2019年1月~2020年6月收治的2型糖尿病合并稳定性心功能不全患者106例为研究对象,采用随机数字表法将患者分为两组,所有患者均给予2型糖尿病饮食控制治疗方案,并给予心功能不全对症药物治疗。对照组患者在此基础上给予二甲双胍,观察组在对照组的基础上给予SGLT2抑制剂达格列净。比较两组患者的血糖、血尿酸（uric acid,UA）、血清脑钠肽(brainnatriureticpeptide,BNP)水平、心脏功能及生活质量。结果：治疗前两组的餐后2 h血糖（2- hour postprandial glucose,2 h PBG）、空腹血糖（fasting blood glucose,FBG）及糖化血红蛋白（glycosylated hemoglobin,HbAIc）水平比较无差异（P＞0.05）,治疗后两组的上述指标均显著降低,且观察组显著低于对照组（P<0.05）;治疗前两组的UA和BNP水平比较无差异（P＞0.05）,治疗后两组的上述指标均显著降低,且观察组显著低于对照组（P<0.05）;治疗前两组的左室射血分数（left ventricular ejection fraction,LVEF）和左室舒张末期内径（left ventricular end diastolic diameter,LVEDD）水平比较无差异（P＞0.05）,治疗后观察组的LVEF水平显著升高,LVEDD水平显著降低（P<0.05）,但对照组治疗前后比较无差异（P＞0.05）;治疗前两组的SF-36健康调查量表(the SF-36 Health Survey,SF-36)评分比较无差异（P＞0.05）,治疗后两组的SF-36评分均显著上升,且观察组显著高于对照组（P<0.05）,两组的不良反应发生率比较无统计学差异（P＞0.05）。结论：达格列净可显著改善2型糖尿病合并稳定性心功能不全患者的血糖、血尿酸水平,还能够改善患者的心脏功能,值得临床借鉴。     

Nondestructive Measurement of Retinal Glucose Transport and Consumption In Vivo Using NMR Spectroscopy

Abstract: The cellular events underlying various retinopathies are poorly understood but likely involve perturbation of retinal glucose metabolism. Current methods for assessing this metabolism are destructive, thus limiting longitudinal studies. We hypothesize that following an intravitreous injection, the clearance rate of a glucose analogue will be a nondestructive index of retinal glucose transport and metabolism in vivo. First, radiolabeled glucose analogues were injected into the vitreous. After 40 min, the dominant clearance path was posterior via the retina and was consistent with a facilitated transport mechanism. Next, either [6,6-²H₂]glucose or 3-deoxy-3-fluoro- d -glucose was injected into the vitreous of rabbit eyes, and the clearance rate of each analogue was determined over 40 min using, respectively, ²H or ¹⁹F NMR. These rates were interpreted as a function of the retinal glucose transport and consumption. From the NMR data, the rate of retinal glucose consumption was ∼16 times slower than the transport of glucose. These data demonstrate that NMR measurements of glucose analogue clearance rate from the vitreous can provide a nondestructive index of retinal glucose transport and consumption in vivo.     

Effect of Acarbose on the Increased Plasma Concentration of Uric Acid Induced by Sucrose Ingestion

Sucrose is converted fructose and glucose, which may increase plasma uric acid concentration (pUA) through increased purine degradation and/or decreased uric acid (UA) excretion. To investigate effects of acarbose, an inhibitor of alpha-glucosidase, on the increased pUA from sucrose administration, we measured pUA and urinary UA excretion in 6 healthy subjects before and after administering sucrose, with and without co-administration of acarbose. Sucrose raised pUA by 10% (p < 0.01). However, excretion and fractional clearance of UA were unchanged. Sucrose and acarbose coadministration also increased pUA, but less than did sucrose alone (sucrose: 4.9 to 5.4 mg/dl; sucrose + acarbose, 4.7 to 4.9 mg/dl, p < 0.05) without changes in urinary excretion and fractional clearance of UA. Acarbose appears to attenuate the rise in pUA by sucrose ingestion by inhibiting sucrose absorption.     

血尿酸水平与缺血性卒中相关分析

目的:研究血尿酸水平与缺血性卒中的相关性。方法:选择缺血性卒中患者(病例组)100例和健康体检者(对照组)100例,分别测定空腹血尿酸(UA)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL-C)、高密度脂蛋白(HDL-C),并对病例组进行颈部动脉超声检查、NIHSS评分、BI指数计算。比较两组尿酸水平及病例组不同血尿酸水平下UA、TC、TG、LDL-C、HDL-C的指标变化及NIHSS评分、BI指数、颈部血管斑块形成率的差别。结果:病例组和对照组空腹血尿酸升高的例数,分别为46例和17例,分别占46%和17%;血尿酸平均浓度分别为485.96±76.03(μmoL/L)和343.12±61.46(μmoL/L),差异有统计学意义。病例组尿酸结果明显高于对照组,两组比较有显著性差异(P<0.01);病例组UA、TC、TG、LDL-C、HDL-C水平较正常对照组差异有显著意义(P<0.05)。对病例组血尿酸水平,颈部血管超声结果、NIHSS评分、BI指数进行分析。病例组患者血尿酸水平与病情及预后有平行关系,即血尿酸水平高,颈部血管斑块形成率高,病情重,预后差。结论:高尿酸血症(HUA)是缺血性卒中重要的危险因素,是防治缺血性卒中的综合因素之一。     

血脂与血尿酸浓度变化在老年脂肪肝患者诊断中的价值

目的：研究血脂与血尿酸浓度变化在老年脂肪肝患者诊断中的价值。方法：选取我院三年来健康体检时确诊为脂肪肝患者 的80 例为观察组,体检结果为健康正常人的80 例为对照组。测定两组总胆固醇、甘油三酯、血尿酸、高密度脂蛋白胆固醇、低密 度脂蛋白胆固醇的值,将检测结果进行对比。结果：两组检测结果对比,观察组的总胆固醇高于对照组的(x2=11.358,P=0.015);观 察组的甘油三酯值高于对照组（x2=7.456,P=0.035）;观察组中的血尿酸,高于对照组值（x2=9.875,P=0.029）、低密度脂蛋白胆固醇 的值,高于对照组（x2=12.037,P=0.013）,高密度脂蛋白胆固醇低于对照组（x2=5.149,P=0.041）。在轻、中、重度三组脂肪肝患者中, 中度脂肪肝患者的总胆固醇、甘油三酯、血尿酸、低密度脂蛋白含量高于轻度脂肪肝患者,高密度脂蛋白含量低于轻度脂肪肝患 者,P＜0.05,差异有统计学意义;重度脂肪肝患者的总胆固醇、甘油三酯、血尿酸、低密度脂蛋白含量高于中度脂肪肝患者,高密度 脂蛋白含量低于中度脂肪肝患者,P＜0.05,差异有统计学意义。结论：脂肪肝病变程度越大,脂肪肝患者总胆固醇、甘油三酯、血尿 酸、低密度脂蛋白胆固醇的值越高,高密度脂蛋白胆固醇的值越低,血脂与血尿酸浓度变化可作为诊断脂肪肝疾病的依据,可实 现早发现、早治疗,值得应用。     

太赫兹(THz)光谱在生物大分子研究中的应用

太赫兹(THz)辐射是一种新型的远红外相干辐射源,近年来,在生物大分子研究中得到了广泛的应用,特别是在生物分子的结构和动力学特性等方面有着巨大的应用潜力.结合THz光谱的特点,介绍了利用THz光谱对蛋白质、糖类及DNA等生物大分子的探索研究,以及THz技术在测定水环境与生物分子相互作用等方面的应用.探讨了该技术在生物学领域应用中有待解决的问题及发展前景.     

Detection of living cervical cancer cells by transient terahertz spectroscopy

The photonic energy of terahertz wave is in the same order of magnitude as the rotational and vibrational energy levels of organic and biological macromolecules, so it has unique advantages in detecting cells and biological macromolecules. However, in the life environment, the dynamic time scale of cell-environment interaction and structural conformation change of biological macromolecules are within picosecond to millisecond, and water has strong absorption to terahertz wave, which has become the bottleneck problem for the detection of cells and biological macromolecules by terahertz technology. In this article, we developed a set of terahertz single measurement system based on the tilt wave front of grating pulse technique. The system was employed for the terahertz detection of trace living cervical cancer cells. We achieved transient detection of the terahertz pulse time-domain waveform of the living HeLa cells. The characteristic absorption peaks were identified by Lambert-Beer law, respectively, at 0.49, 0.71, 1.04, 1.07, 1.26 and 1.37 THz. The absorbance is proportional to the cell concentration.     

高尿酸血症患者血清尿酸水平与糖耐量异常、炎症因子及红细胞参数的相关性分析

摘要 目的：探讨高尿酸血症（HUA）患者血清尿酸（UA）水平与糖耐量异常、炎症因子及红细胞参数的相关性。方法：选取2020年1月~2021年1月期间我中心在健康体检中诊断的HUA患者240例（观察组）,另选取同期在我中心体检的健康志愿者200例（对照组）,分别检测血清UA、炎症因子：超敏C反应蛋白（hs-CRP）、单核细胞趋化蛋白1（MCP-1）、白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、红细胞参数：红细胞分布宽度（RDW）、红细胞平均体积（MCV）及红细胞计数、糖耐量指标：空腹血糖（FPG）、餐后2h血糖（2hPG）及空腹胰岛素（FINS）,计算稳态模型胰岛素抵抗指数（HOMA-IR）和稳态模型胰岛素敏感指数（HOMA-ISI）。结果：观察组的UA、RDW及红细胞计数均高于对照组,MCV低于对照组（P<0.05）。观察组的hs-CRP、MCP-1、IL-6及TNF-α均高于对照组（P<0.05）。观察组的FPG、2hPG、FINS及HOMA-IR均高于对照组,HOMA-ISI低于对照组（P<0.05）。Pearson相关系数指出,HUA患者血清UA水平与红细胞计数、RDW、hs-CRP、MCP-1、IL-6、TNF-α、FPG、2hPG、FINS及HOMA-IR呈正相关,而与HOMA-ISI、MCV呈负相关（P<0.05）。结论：高尿酸水平可引起HUA患者炎症反应增强、糖耐量异常及红细胞参数改变,控制UA水平可减少多种并发症的发生风险。     

尿酸氧化酶基因的克隆、表达及其产物的应用

克隆了产朊假丝酵母(Candida utilis)AS2-117尿酸氧化酶(Urate Oxidase,Uricase,EC1.7.3.3)的基因。将此基因插入原核表达质粒pET21a后转化大肠杆菌BL21(DE3),获得高表达的重组转化子菌株。经IPTG诱导,重组尿酸酶基因表达量可达菌体可溶性蛋白的40%。重组尿酸氧化酶为有酶活性的可溶蛋白。Western印迹分析证实表达产物有免疫学活性。经DEAE DE52纤维素离子交换柱层析纯化,目的蛋白纯度可达95%。重组蛋白和天然蛋白的理化特征比较证明重组蛋白的热稳定性有较大提高。酶盒配制和临床应用实验表明重组蛋白可代替天然蛋白进行临床血清尿酸的分析。     

脑小血管病患者血清尿酸水平和步态障碍之间的相关性

目的:探讨脑小血管病(Cerebral small vessel disease,CSVD)患者血清尿酸(Uric acid,UA)水平和步态障碍之间的相关性。方法:将我院自2018年1月至2019年1月收治的CSVD患者172例作为研究对象,根据患者血清尿酸水平分为研究组87例,对照组85例。收集和比较两组的临床资料,使用Logistic回归分析血清尿酸和CSVD患者脑室旁、深部白质高信号、步态障碍之间的相关性。结果:两组的年龄、性别、体质指数、血糖指标、血脂指标水平,合并高血压、糖尿病病史和吸烟情况比较差异无统计学意义(P0.05)。研究组血清尿酸水平、饮酒患者比例明显高于对照组(P0.05),脑室旁高信号和深部白质高信号中重度比例均明显高于对照组(P0.05);将步态障碍、脑室旁高信号与深部白质高信号作为影响因素带入相关分析,结果显示血清尿酸水平与步态障碍、脑室旁高信号与深部白质高信号比较存在正相关(P0.05)。结论:CSVD患者血清高尿酸水平与脑室旁、深部白质高信号病变程度呈明显的正相关性,也是患者步态障碍的影响因素。