微创穿刺引流联合开颅血肿清除术对高血压脑出血合并脑疝患者神经功能、炎症反应及脑部血流的影响

摘要 目的：探讨开颅血肿清除术联合微创穿刺引流对高血压脑出血（HICH）合并脑疝患者神经功能、炎症反应及脑部血流的影响。方法：回顾性选择2014年4月~2019年11月期间我院收治的HICH合并脑疝患者80例,按照手术方式的不同分为A组（n=38,行开颅血肿清除术）和B组（n=42,行微创穿刺引流联合开颅血肿清除术）,对比两组疗效、神经功能、炎症反应、脑部血流及预后情况。结果：B组的总有效率为92.86%（39/42）,高于A组的76.32%（29/38）,差异有统计学意义（P<0.05）。两组术后7 d血清神经元特异性烯醇化酶（NSE）、S100β蛋白水平以及术后3个月美国国立卫生研究院卒中量表（NIHSS）评分均较术前降低,且B组低于A组（P<0.05）。两组术后7 d血清白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、超敏-C反应蛋白（hs-CRP）均较术前降低,且B组低于A组（P<0.05）。两组术后1个月、术后3个月大脑中动脉平均流速（Vm）均较术前增加,且B组高于A组（P<0.05）;两组术后1个月、术后3个月大脑中动脉搏动指数（PI）较术前降低,且B组低于A组（P<0.05）。两组预后良好率无差异（P>0.05）。结论：与开颅血肿清除术相比,开颅血肿清除术联合微创穿刺引流治疗HICH合并脑疝患者可有效恢复患者脑部血流速度,降低炎症反应,有利于患者神经功能的恢复。     

不同时机行血管介入栓塞术治疗颅内动脉瘤的疗效及对患者预后、神经功能和血清炎性因子的影响

摘要 目的：探讨不同时机行血管介入栓塞术治疗颅内动脉瘤的疗效及对患者预后、神经功能和血清炎性因子的影响。方法：选择2019年3月到2020年12月期间我院收治的80例颅内动脉瘤患者,按手术时间的不同将其分为早期组、延期组,其中早期组36例,发病至手术时间≤72 h;延期组44例,发病至手术时间＞72 h,对比两组疗效、预后、神经功能、血清炎性因子及并发症发生率。结果：早期组的完全栓塞率高于延期组,基本栓塞率低于延期组（P<0.05）。两组术后3个月美国国立卫生研究院卒中量表（NIHSS）、改良Rankin量表评分均较术前下降,且早期组低于延期组（P<0.05）。早期组的预后良好率高于延期组（P<0.05）。两组术后3 d血清白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）水平下降,且早期组低于延期组（P<0.05）,白介素-10（IL-10）水平升高,且早期组高于延期组（P<0.05）。早期组的并发症发生率低于延期组（P<0.05）。结论：早期行血管介入栓塞术治疗颅内动脉瘤患者,可提高完全栓塞率,减轻神经功能损伤及炎性应激,降低并发症的发生风险,促进预后和生活质量改善。     

针刺运动疗法联合早期康复训练对急性踝关节扭伤患者踝关节功能、血清炎症因子和致痛物质水平的影响

摘要 目的：观察针刺运动疗法联合早期康复训练对急性踝关节扭伤患者踝关节功能、血清炎症因子和致痛物质水平的影响。方法：选取湖南中医药大学第一附属医院2019年5月~2022年1月期间收治的116例急性踝关节扭伤患者。按照随机数字表法分为对照组（早期康复训练,n=58）和研究组（针刺运动疗法联合早期康复训练,n=58）。观察两组治疗前、治疗4周后的疗效、量表评分[视觉模拟评分（VAS）、美国足与踝关节协会（AOFAS）踝-后足功能评分]、踝关节功能、血清炎症因子[白细胞介素（IL）-1β、IL-6和肿瘤坏死因子-α（TNF-α）]和致痛物质[神经肽（NPY）、P物质（SP）]水平。结果：研究组的临床总有效率为96.55%,高于对照组的77.59%,差异有统计学意义（P<0.05）。治疗4周后,研究组的AOFAS评分高于对照组（P<0.05）,VAS评分低于对照组（P<0.05）,血清IL-6、TNF-α、IL-1β水平低于对照组（P<0.05）,踝关节背伸活动度、踝关节跖屈活动度大于对照组（P<0.05）,血清NPY、SP水平低于对照组（P<0.05）。结论：急性踝关节扭伤患者经针刺运动疗法联合早期康复训练干预后,可有效降低其血清致痛物质和炎症因子水平,有利于疼痛症状的缓解及踝关节功能的恢复。     

腔镜下腺体切除术对早期乳腺癌患者血清免疫球蛋白及TNF-α、IL-10水平变化的影响

摘要 目的：分析腔镜下腺体切除术对早期乳腺癌患者血清免疫球蛋白及TNF-α、IL-10水平的影响,从而对其优势评估。方法：选择2017年2月-2020年2月于本院实施乳腺癌手术患者100例,根据其选择手术方式的不同分为2组：A组（腔镜下腺体切除术,59例）和B组（开放乳房皮下腺体切除术,41例）,分别统计患者手术时间、术后拔管时间以及住院时间;术后1个月,取患者外周血,离心取血清,采用免疫比浊法检测患者血清免疫功能相关指标IgM和IgG含量、采用人酶联免疫吸附实验（ELISA）试剂盒检测患者血清中炎症反应指标TNF-α和IL-10含量、统计术后两组患者出现术野皮下出血、皮下积液、乳头乳晕坏死等并发症的例数;术后一年,统计两组患者出现复发和淋巴结转移等现象的例数。结果：A组患者手术时间显著长于B组,而其拔管时间和住院时间均显著短于B组（P＜0.05）。A组并发症发生率（5.00 %）显著高于B组（25.71%）（P<0.05）。术前1 d,两组患者血清免疫指标IgM和IgG水平和炎症反应指标TNF-α和IL-10水平相比差异无统计学意义（P＞0.05）,而术后3 d~术后1 m,A组患者血清免疫指标IgM和IgG水平以及抗炎因子IL-10水平均显著高于B组,促炎因子TNF-α水平显著低于B组（P＜0.05）。A组患者术后1年内乳腺癌复发率（3.3%）与B组（10.0%）相比差异不具有统计学意义（P＞0.05）。结论：腔镜下腺体切除术治疗早期乳腺癌具有拔管时间以及术后住院时间短、并发症发生率低等优势,其原因可能与该手术对患者血清免疫球蛋白IgM和IgG及炎症因子TNF-α、IL-10水平影响程度较小、术后恢复较快有关。     

通滞苏润江胶囊联合塞来昔布对早期膝骨关节炎患者血清炎症因子和疼痛介质的影响

摘要 目的：观察通滞苏润江胶囊联合塞来昔布对早期膝骨关节炎（KOA）患者血清炎症因子和疼痛介质的影响。方法：选择2021年6月-2022年12月期间石家庄市人民医院收治的早期KOA患者80例,采用随机数字表法将患者分为对照组（塞来昔布,40例）和观察组（通滞苏润江胶囊联合塞来昔布,40例）。对比两组疗效、疼痛视觉模拟评分（VAS）、西安大略和麦克马斯特大学骨关节炎指数（WOMAC）评分、炎症因子和疼痛介质。结果：观察组临床总有效率高于对照组（P<0.05）。两组治疗1个月后VAS、WOMAC评分下降,且观察组低于对照组同时间点（P<0.05）。两组治疗1个月后肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）、白细胞介素-6（IL-6）下降,且观察组低于对照组同时间点（P<0.05）。两组治疗1个月后前列腺素E₂（PGE₂）、P物质（SP）下降,且观察组低于对照组同时间点（P<0.05）。两组不良反应发生率对比未见统计学差异（P>0.05）。结论：塞来昔布和通滞苏润江胶囊联合治疗早期KOA患者,可缓解疼痛,提高临床治疗效果,改善关节功能,同时还可改善血清炎症因子和疼痛介质水平。     

神经内镜手术与小骨窗开颅手术治疗高血压脑出血疗效对比的回顾性研究

摘要 目的：回顾性对比神经内镜手术与小骨窗开颅手术治疗高血压脑出血（HICH）疗效。方法：回顾性选取2018年7月~2021年3月期间在联勤保障部队第909医院治疗的83例HICH患者的临床资料。根据手术方式的不同,将患者分为A组（n=41）和B组（n=42）,A组患者采用小骨窗开颅手术治疗,B组患者采用神经内镜手术治疗,对比两组围术期指标、并发症发生率、神经功能、生活能力、神经损伤指标及预后。结果：与A组相比, B组的手术时间、住院时间明显缩短,术中出血量减少,血肿清除率升高（P<0.05）。B组术后1周美国国立卫生研究院卒中量表（NIHSS）评分低于A组,Barthel指数评分高于A组（P<0.05）。B组术后1周神经元特异性烯醇化酶（NSE）、S100B 蛋白（S100B）、髓鞘碱性蛋白（MBP）、胶质纤维酸性蛋白（GFAP）水平低于A组（P<0.05）。B组的并发症发生率小于A组（P<0.05）。B组的预后良好率高于A组（P<0.05）。结论：神经内镜手术、小骨窗开颅手术治疗HICH均可获得较好的疗效,其中神经内镜手术在缩短手术时间、住院时间,减少术中出血量和并发症发生率,提高血肿清除率,减轻神经功能损伤,促进患者生活能力改善,改善患者预后方面的效果更为显著。     

丙泊酚靶控输注联合右美托咪定对颅脑外伤颅内血肿清除术患者血清炎症因子和脑损伤指标的影响

摘要 目的：观察丙泊酚靶控输注联合右美托咪定对颅脑外伤颅内血肿清除术患者血清炎症因子和脑损伤指标的影响。方法：选择2016年3月~2021年5月期间联勤保障部队第901医院麻醉科收治的颅脑外伤颅内血肿清除术患者115例。采用随机数字表法将患者分为对照组和实验组,例数分别为57例和58例。对照组患者接受丙泊酚靶控输注,实验组患者接受丙泊酚靶控输注联合右美托咪定。对比两组苏醒质量（苏醒时间、听指令睁眼时间、滞留苏醒室时间）、血流动力学指标[心率（HR）、收缩压（SBP）、舒张压（DBP）]、炎症因子[白介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）、白介素-6（IL-6）]、脑损伤指标[神经元特异性烯醇化酶（NSE）、S100β、脑源性神经营养因子（BDNF）]情况,同时观察两组围术期不良反应情况。结果：实验组的苏醒时间、听指令睁眼时间、滞留苏醒室时间短于对照组（P<0.05）。实验组气管插管时（T1）~拔管后（T4）时间点HR、SBP、DBP低于对照组（P<0.05）。实验组术后48hIL-1β、TNF-α、IL-6低于对照组（P<0.05）。实验组术后48hNSE、S100β低于对照组,BDNF高于对照组（P<0.05）。两组不良反应发生率组间对比未见差异（P>0.05）。结论：丙泊酚靶控输注联合右美托咪定应用于颅脑外伤颅内血肿清除术患者,可维持机体血流动力学稳定,减轻炎症反应和脑损伤,促进术后苏醒,且不良反应发生率无明显增加。     

急性脑梗死患者血清H-FABP、干扰素-γ、半胱氨酸和Ang-1联合检测及其临床意义

摘要 目的：探讨急性脑梗死患者血清心型脂肪酸结合蛋白（H-FABP）、干扰素-γ（IFN-γ）、同型半胱氨酸（Hcy）、血管生成素-1（Ang-1）联合检测及其临床意义。方法：选取本院自2018年4月-2021年4月收治的66例急性脑梗死患者的临床资料,将其作为研究组。同时选取同期来院体检的健康者66例为对照组,均通过酶联免疫吸附试验试剂盒检测H-FABP、IFN-γ、Hcy、Ang-1水平,比较各组检测水平,分析联合检测意义。结果：研究组患者的H-FABP、IFN-γ、Hcy水平均高于对照组相应指标,Ang-1水平低于对照组水平,差异均具有统计学意义（P＜0.05）;H-FABP、IFN-γ、Hcy、Ang-1水平在不同病情间差异具有统计学意义（P＜0.05）,其中与轻度、中度相比,重度患者的H-FABP、IFN-γ、Hcy水平更高,Ang-1水平更低,差异具有统计学意义（P<0.05）;急性脑梗死患者病情与H-FABP、IFN-γ、Hcy呈正相关,与Ang-1呈负相关,有统计学意义（P<0.05）;急性脑梗死患者H-FABP与IFN-γ、Hcy指标相互间呈现正相关关系,与Ang-1呈现负相关关系（P<0.05）。结论：急性脑梗死患者联合检测H-FABP、IFN-γ、Hcy、Ang-1水平具有重要意义,可作为疾病早期诊断的重要指标。     

贮存式自体输血和异体输血对老年脑外科手术患者炎症反应及T淋巴细胞亚群的影响

摘要 目的：探讨老年脑外科手术患者分别经贮存式自体输血和异体输血后,其对机体T淋巴细胞亚群和炎症反应的影响。方法：选取2017年3月~2019年10月期间我院收治的行脑外科手术老年患者150例,根据随机数字表法将患者分为对照组（n=75,异体输血）和研究组（n=75,贮存式自体输血）,对比两组围术期相关指标情况,比较两组术前、术后5d的炎症因子水平[白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、C反应蛋白（CRP）]以及T淋巴细胞亚群变化情况,记录两组输血不良反应发生情况。结果：两组术前住院时间、术前血红蛋白比较差异无统计学意义（P>0.05）;研究组术后住院时间短于对照组,术中出血量、术中输血量少于对照组,术后血红蛋白多于对照组（P<0.05）。两组术后5d IL-6、CRP、TNF-α均升高,但研究组低于对照组（P<0.05）。两组患者术后5d CD3⁺、CD4⁺/CD8⁺、CD4⁺均降低,但研究组高于对照组,CD8⁺升高,但研究组低于对照组（P<0.05）。研究组输血不良反应发生率低于对照组（P<0.05）。结论：与异体输血应用于老年脑外科手术患者相比,贮存式自体输血效果确切,可减轻炎性应激,降低免疫抑制,同时还可减少输血不良反应发生率,节约宝贵的血液资源。     

脉络舒通丸联合阿托伐他汀对冠心病PCI术患者血脂、炎症因子及术后再狭窄的影响

摘要 目的：探讨脉络舒通丸联合阿托伐他汀对冠心病经皮冠状动脉介入（PCI）术患者血脂、炎症因子及术后再狭窄的影响。方法：选择2018年5月~2020年2月期间我院接收的冠心病PCI术患者93例,分为A、B两组,A组（46例）给予阿托伐他汀治疗,B组（47例）给予脉络舒通丸联合阿托伐他汀治疗,比较两组患者临床疗效、心电图疗效、血脂、炎症因子及术后再狭窄发生率。结果：B组治疗2个月后的临床总有效率为93.62%（44/47）,高于A组的76.09%（35/46）（P<0.05）。B组治疗2个月后的心电图总有效率为89.36%（42/47）,高于A组的67.39%（31/46）（P<0.05）。治疗2个月后两组高密度脂蛋白胆固醇（HDL-C）升高,白介素-6（IL-6）、胆固醇（TC）、C反应蛋白（CRP）、肿瘤坏死因子-α（TNF-α）、低密度脂蛋白胆固醇（LDL-C）、三酰甘油（TG）降低（P<0.05）,治疗2个月后B组TC、TG、LDL-C、IL-6、CRP、TNF-α低于A组,HDL-C高于A组（P<0.05）。B组术后再狭窄发生率为6.38%（3/47）,明显低于A组的23.91%（11/46）,差异有统计学意义（P<0.05）。结论：脉络舒通丸联合阿托伐他汀治疗冠心病PCI术患者,疗效满意,可有效改善心电图疗效、血脂、炎症因子水平,并降低术后再狭窄发生率。     

Interactions of the DNA intercalator acridine orange, with itself, with caffeine, and with double stranded DNA

Caffeine (CAF) inhibits the intercalation of acridine orange (AO) into cellular DNA. Optical absorption and fluorescence spectroscopy were employed to determine the molecular interactions of AO with itself, with CAF, and with double stranded herring sperm DNA (dsDNA). AO dimerization was observed at concentrations >2 micromol. The sharp increase in fluorescence (lambda(em)=530 nm) at 5 micromol of AO was attributed to AO multimer formation. From 0.5 to 5.0 micromol, the AO self-association binding constant (K(assoc)) was determined to be 38620 mol(-1), however, the presence of 150 mmol NaCl increased K(assoc) to 118000 mol(-1) attributed to the charge neutralization. The K(assoc) for AO with CAF was confirmed to be 256 mol(-1). K(assoc) for the binding of AO with 20 micromol DNA ranged from, 32000 mol(-1) at 2 micromol AO, to approximately 3700 mol(-1) at 10 micromol AO, in the absence of NaCl. This AO concentration dependency of K(assoc) value with DNA was attributed to AO intercalation into dsDNA at high dsDNA/AO ratios, and electrostatic binding of AO to dsDNA at low AO ratios. The findings provide information used to explain fluorescence intensity values at lambda(em) at 530 nm from studies that combine AO, caffeine, and dsDNA.     

Interaction of tRNA with Safranal,Crocetin, and Dimethylcrocetin

Abstract

Saffron is the red dried stigmas of Crocus sativus L. flowers and used both as a spice and as a drug in traditional therapeutic. The biological activity of saffron in modern medicine is in development. Its numerous applications as an anti-oxidant and anti-cancer agent are due to its secondary metabolites and their derivatives (safranal, crocins, crocetin, dimethylcrocetin). The aim of this study was to examine the interaction of transfer RNA with safranal, crocetin, and dimethylcrocetin in aqueous solution at physiological conditions. Constant tRNA concentration (6.25 mM) and various drug/tRNA (phosphate) molar ratios of 1/48 to 1/8 were used. FT-IR and UV-Visible difference spectroscopic methods have been applied to determine the drug binding mode, the binding constants and the effects of drug complexation on the stability and conformation of tRNA duplex. External binding mode was observed for safranal crocetin and dimethylcrocetin, with overall binding constants K_safranal = 6.8 (± 0.34) × 10³ M^?1, K_CRT = 1.4 (± 0.31) × 10⁴ M^?1, and K_DMCRT = 3.4 (± 0.30) × 10⁴ M^?1. Transfer RNA remains in the A-family structure, upon safranal, crocetin and dimethylcrocetin complexation.     

Linkage relations of JK, CO, KEL and IGK with each other and with AHCY

Linkage analyses of locus pairs involving IGK, JK, CO, KEL and AHCY resulted in altogether negative lod scores, thereby dwindling the reported linkage relations.     

Kymographs,stimulators, and kymographs with stimulators

This biology investigation on Pristipomoides filamentosus larval development, survival, and aquaculture research was developed with three educational objectives: to provide high school students with (1) a scientific background on the biology and science of fisheries as well as overfishing, its consequences, and possible mitigations; (2) exposure to field and laboratory techniques in marine science; and (3) practical skills in scientific inquiry and investigation. We teach this investigation at the Hawai‘i Institute of Marine Biology, where we have access to captive broodstock of the pink snapper, P. filamentosus. During this investigation students follow several steps scientists take to study aquaculture: collecting spawn from outdoor fish pens, quantifying the number of eggs, determining the percentage of fertilisation, and estimating the time of spawning and hatching. Additionally, students perform hypothesis-driven science activities with the embryos to test the effects of water quality on their development and survival. In this paper we discuss background information of aquaculture, specifically of P. filamentosus, and thoroughly describe the several components of delivering the investigation. Lastly, we provide possible outcomes of students’ performances in the laboratory activities, and discuss how effectively the exercise met its educational objectives.     

Carbonic anhydrase inhibitors. Inhibition of isozymes I, II, IV, V, and IX with anions isosteric and isoelectronic with sulfate, nitrate, and carbonate

The inhibition of five human carbonic anhydrase (hCA, EC 4.2.1.1) isozymes; the cytosolic hCA I and II, the membrane-bound hCA IV, the mitochondrial hCA V, and the tumor-associated, transmembrane hCA IX, with anions isosteric and isoelectronic with sulfate, nitrate, and carbonate; such as chlorate, perchlorate, bromate, iodate, periodate, silicate, bismuthate, vanadate, molybdate, and wolframate is reported. Apparently, the geometry of the inhibitor (tetrahedral or trigonal) does not influence its binding to the Zn(II) ion of the enzyme active site, but the nature of the central element is the most important factor influencing potency. Isozymes hCA I and II are best inhibited by chlorate, perchlorate, and silicate, together with the anions structurally related to sulfate, sulfamate, and sulfamidate, but sulfate itself is a weak inhibitor (inhibition constant of 74 mM against hCA I and 183 mM against hCA II). Molybdate is a very weak hCA I inhibitor (K(I) of 914 mM) but it interacts with hCA II (K(I) of 27.5mM). Isozyme IV is well inhibited by sulfate (K(I) of 9 mM), sulfamate, and sulfamidate (in the low micromolar range), but not by perchlorate (K(I) of 767 mM). The mitochondrial isozyme V has the lowest affinity for sulfate (K(I) of 680 mM) and carbonate (K(I) of 95 mM) among all the investigated isozymes, suggesting on one hand its possible participation in metabolon(s) with sulfate anion exchanger(s), and on the other hand an evolutionary adaptation to working at higher pH values (around 8.5 in mitochondria) where rather high amounts of carbonate in equilibrium with bicarbonate may be present. Metasilicate, isosteric to carbonate, is also about a 10 times weaker inhibitor of this isozyme as compared to other CAs investigated here (K(I) of 28.2 mM). Surprisingly, the tumor-associated isozyme IX is resistant to sulfate inhibition (K(I) of 154 mM) but has affinity in the low micromolar range for carbonate, sulfamate, and sulfamidate (K(I) in the range of 8.6-9.6 microM). This constitutes another proof that this isozyme best works at acidic pH values present in tumors, being inhibited substantially at higher pH values when more carbonate may be present. Bromate and chlorate are quite weak CA IX inhibitors (K(I) s of 147-274 mM).     

A pheromonotropic peptide of Helicoverpa zea,with melanizing activity,interaction with PBAN,and distribution of immunoreactivity

The sequence of an 18-amino acid residue peptide was deduced from the gene encoding PBAN and other peptides with common C-termini in Helicoverpa zea. The peptide caused melanization in larvae and pheromone production in females of H. zea, and was designated pheromonotropic melanizing peptide (Hez-PMP). The peptide has a 83% sequence homology with a pheromonotropic peptide isolated from Pseudaletia separata. PMP caused melanization and mortality when injected into larvae just before molting. Whereas intense melanization was caused with a dose of 1,000 pmol, peak mortality occurred at 100 pmol, with 50% of larvae dying within 48 h after injection. Pheromonotropic activity of PMP was dose dependent. Co-injection of Hez-PMP and Hez-PBAN into a female resulted in suppression of the pheromonotropic effect of PBAN. Whole-mount immunocytochemical studies revealed PMP-like immunoreactivity in frontal ganglion, subesophageal, thoracic, and abdominal ganglia as well as the esophageal nerve.     

Titin-cap associates with,and regulates secretion of,Myostatin

Myostatin, a secreted growth factor, is a key negative regulator of skeletal muscle growth. To identify modifiers of Myostatin function, we screened for Myostatin interacting proteins. Using a yeast two-hybrid screen, we identified Titin-cap (T-cap) protein as interacting with Myostatin. T-cap is a sarcomeric protein that binds to the N-terminal domain of Titin and is a substrate of the titin kinase. Mammalian two-hybrid studies, in vitro binding assays and protein truncations in the yeast two-hybrid system verified the specific interaction between processed mature Myostatin and full-length T-cap. Analysis of protein-protein interaction using surface plasmon resonance (Biacore, Uppsala, Sweden) kinetics revealed a high affinity between Myostatin and T-cap with a KD of 40 nM. When T-cap was stably overexpressed in C(2)C(12) myoblasts, the rate of cell proliferation was significantly increased. Western analyses showed that production and processing of Myostatin were not altered in cells overexpressing T-cap, but an increase in the retention of mature Myostatin indicated that T-cap may block Myostatin secretion. Bioassay for Myostatin confirmed that conditioned media from myoblasts overexpressing T-cap contained lower levels of Myostatin. Given that Myostatin negatively regulates myoblast proliferation, the increase in proliferation observed in myoblasts overexpressing T-cap could thus be due to reduced Myostatin secretion. These results suggest that T-cap, by interacting with Myostatin, controls Myostatin secretion in myogenic precursor cells without affecting the processing step of precursor Myostatin.     

Interaction of tRNA with Safranal, Crocetin, and Dimethylcrocetin

Saffron is the red dried stigmas of Crocus sativus L. flowers and used both as a spice and as a drug in traditional therapeutic. The biological activity of saffron in modern medicine is in development. Its numerous applications as an anti-oxidant and anti-cancer agent are due to its secondary metabolites and their derivatives (safranal, crocins, crocetin, dimethylcrocetin). The aim of this study was to examine the interaction of transfer RNA with safranal, crocetin, and dimethylcrocetin in aqueous solution at physiological conditions. Constant tRNA concentration (6.25 mM) and various drug/tRNA (phosphate) molar ratios of 1/48 to 1/8 were used. FT-IR and UV-Visible difference spectroscopic methods have been applied to determine the drug binding mode, the binding constants and the effects of drug complexation on the stability and conformation of tRNA duplex. External binding mode was observed for safranal crocetin and dimethylcrocetin, with overall binding constants K(safranal) = 6.8 (+/- 0.34) x 10(3) M(-1), K(CRT) = 1.4 (+/- 0.31) x 10(4) M(-1), and K(DMCRT) = 3.4 (+/- 0.30) x 10(4) M(-1). Transfer RNA remains in the A-family structure, upon safranal, crocetin and dimethylcrocetin complexation.