多发性骨髓瘤患者骨髓单个核细胞Treg、Th17和血清IL-6、IL-10与临床分期以及治疗效果的关系分析

摘要 目的：探讨多发性骨髓瘤（MM）患者骨髓单个核细胞调节性T细胞（Treg）、辅助性T细胞（Th17）和血清白细胞介素-6（IL-6）、白细胞介素-10（IL-10）与临床分期以及治疗效果的关系。方法：选择2016年3月至2020年12月河北医科大学第一医院收治的MM患者60例为研究对象,检测并对比不同Durie-Salmon分期患者的骨髓单个核细胞Treg、Th17、Treg/Th17及血清IL-6、IL-10水平;患者入院后均给予常规治疗,根据疗效分为有效组和无效组,比较两组治疗前后骨髓单个核细胞Treg、Th17、Treg/Th17及血清IL-6、IL-10水平;分析Treg、Th17、Treg/Th17及血清IL-6、IL-10与MM患者Durie-Salmon分期、治疗效果的相关性。结果：MM患者骨髓单个核细胞Treg、Treg/Th17及血清IL-6、IL-10水平III期组高于II期组,II期组高于I期组（P＜0.05）。有效组治疗后骨髓单个核细胞Treg、Treg/Th17水平及血清IL-6、IL-10水平较治疗前明显降低（P＜0.05）;治疗后,骨髓单个核细胞Treg、Treg/Th17及血清IL-6、IL-10水平无效组高于有效组（P＜0.05）。骨髓单个核细胞Treg、Treg/Th17及血清IL-6、IL-10水平与MM患者Durie-Salmon分期呈正相关,与治疗效果呈负相关（P＜0.05）;骨髓单个核细胞Th17水平与MM患者的Durie-Salmon分期、治疗效果无明显的相关性（P＞0.05）。结论：骨髓单个核细胞Treg、Treg/Th17水平及血清IL-6、IL-10水平与MM患者肿瘤临床分期、治疗效果密切相关,检测其水平可对MM的临床治疗及预后起到一定评估作用。     

电针深刺八髎穴对脾肾阳虚型溃疡性结肠炎患者Th17/Treg细胞免疫平衡和血清炎症因子的影响

摘要 目的：观察电针深刺八髎穴对脾肾阳虚型溃疡性结肠炎（UC）患者的治疗效果,并探讨其作用机制。方法：选取自2020年3月~2021年2月期间天津市人民医院收治的80例脾肾阳虚型UC患者。采用随机数字表法分为对照组和研究组2组,各为40例,对照组接受常规西医治疗,研究组在常规西医治疗基础上联合电针深刺八髎穴治疗,对比两组患者疗效、中医证候积分、血清炎症因子水平、Th17/Treg细胞。结果：与对照组相比,研究组可进一步提高临床总有效率（P<0.05）。治疗2周后,研究组畏寒肢冷、腹部冷痛、晨起泄泻评分低于对照组（P<0.05）。治疗2周后,研究组血清?酌-干扰素（IFN-γ）、白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）水平低于对照组（P<0.05）。治疗2周后,研究组Th17细胞水平、Th17/Treg比值低于对照组,Treg细胞水平高于对照组（P<0.05）。结论：电针深刺八髎穴可促进脾肾阳虚型UC患者症状改善,同时该治疗方案还具有调节Th17/Treg细胞免疫平衡,降低血清炎症因子水平的作用。     

不明原因复发性流产再次妊娠患者血清1,25(OH)2D3、sTim-3与Th17/Treg免疫失衡和妊娠结局的关系

摘要 目的：探讨不明原因复发性流产（URSA）再次妊娠患者血清1,25-二羟维生素D3[1,25（OH)）₂D₃]、可溶性T细胞免疫球蛋白黏蛋白分子3（sTim-3）与辅助性T细胞17（Th17）/调节性T细胞（Treg）免疫失衡和妊娠结局的关系。方法：选择于湖南省妇幼保健院2020年1月~2022年1月就诊的62例URSA再次妊娠患者作为研究组,另选择同期进行孕检的正常早孕妇女30例作为对照组。比较两组孕早期血清1,25(OH) ₂D₃、sTim-3及外周血Th17细胞、Treg细胞水平、Th17/Treg比值。Pearson法分析URSA再次妊娠患者血清1,25(OH) ₂D₃、sTim-3与外周血Th17细胞、Treg细胞水平、Th17/Treg比值平的相关性。根据URSA再次妊娠患者妊娠结局的不同分为妊娠成功分娩组和妊娠再次流产组,比较两组孕早期血清1,25(OH) ₂D₃、sTim-3与外周血Th17细胞、Treg细胞水平、Th17/Treg比值。受试者工作特征（ROC）曲线分析血清1,25(OH) ₂D₃、sTim-3与外周血Th17细胞、Treg细胞水平、Th17/Treg比值对妊娠结局的预测价值。结果：研究组血清sTim-3、外周血Th17细胞水平、Th17/Treg比值高于对照组,血清1,25(OH) ₂D₃、外周血Treg细胞水平低于对照组（P<0.05）。Pearson相关分析显示,URSA再次妊娠患者血清1,25(OH) ₂D₃与血清sTim-3、外周血Th17细胞水平、Th17/Treg比值呈负相关,与Treg细胞水平呈正相关（P<0.05）;血清sTim-3与外周血Treg细胞水平呈负相关,与Th17细胞水平、Th17/Treg比值呈正相关（P<0.05）。妊娠再次流产组血清sTim-3、外周血Th17细胞水平、Th17/Treg比值高于妊娠成功分娩组,血清1,25(OH) ₂D₃、外周血Treg细胞水平低于妊娠成功分娩组（P<0.05）。ROC曲线分析显示,血清1,25(OH) ₂D₃、sTim-3及外周血Th17细胞、Treg细胞水平及Th17/Treg比值均可预测URSA再次妊娠患者妊娠再次流产的发生风险,且上述指标联合检测的预测效能更高。结论：血清1,25(OH) ₂D₃水平异常降低、sTim-3水平异常升高可导致Th17/Treg免疫失衡,导致URSA再次妊娠患者再次发生流产。上述指标联合检测对URSA再次妊娠患者妊娠再次流产的预测效能更高。     

桥本甲状腺炎患者血清miR-326、miR-155与甲状腺相关抗体和Th17/Treg细胞因子失衡的相关性分析

摘要 目的：探讨桥本甲状腺炎（HT）患者血清微小核糖核酸（miR）-326、miR-155与甲状腺相关抗体和辅助性T细胞17（Th17）/调节性T细胞（Treg）细胞因子失衡的相关性。方法：选择2021年1月至2022年10月空军军医大学唐都医院收治的HT患者82例作为研究组，同期接受体检的健康人80例作为对照组，比较两组血清miR-326、miR-155、甲状腺功能参数[促甲状腺激素（TSH）、游离三碘甲状原氨酸（FT₃）、游离甲状腺素（FT₄）]、甲状腺相关抗体[甲状腺过氧化物酶抗体（TPOAb）、甲状腺球蛋白抗体（TGAb）]、Th17、Treg水平及其细胞因子水平，并分析HT患者血清miR-326、miR-155与甲状腺相关抗体和Th17/Treg细胞因子失衡的相关性。结果：研究组TSH、TPOAb、TGAb显著高于对照组，FT₃、FT₄显著低于对照组（P<0.05）。研究组血清miR-326、miR-155表达水平显著高于对照组（P<0.05）。研究组Th17、Th17/Treg、白细胞介素-17（IL-17）、γ干扰素（IFN-γ）显著高于对照组，Treg、白细胞介素-10（IL-10）水平显著低于对照组（P<0.05）。Pearson相关分析显示，HT患者血清miR-326、miR-155分别与TSH、TPOAb、TGAb、Th17、Th17/Treg、IL-17、IFN-γ呈正相关，与FT₃、FT₄、Treg、IL-10呈负相关（P<0.05）。结论：HT患者血清miR-326、miR-155水平异常升高，其水平与TPOAb、TGAb自身抗体及Th17/Treg失衡相关，血清miR-326、miR-155可能通过影响Th17/Treg免疫平衡，促进HT的发生和发展。     

宫腔灌注HCG对反复种植失败患者子宫内膜血流、Th17细胞和妊娠结局的影响

摘要 目的：观察宫腔灌注人绒毛膜促性腺激素（HCG）对反复种植失败（RIF）患者子宫内膜血流、辅助性T细胞17（Th17）和妊娠结局的影响。方法：回顾性分析连云港市妇幼保健院2020年3月~2022年12月期间收治的RIF行冻融囊胚移植的患者148例。根据冻融囊胚移植前是否进行宫腔灌注HCG分为对照组（n=71）和研究组（n=77），对照组接受常规子宫内膜准备方案，研究组则在对照组的基础上接受宫腔灌注HCG治疗。对比两组子宫内膜螺旋动脉血流参数、Th17细胞因子和妊娠结局。结果：两组移植后搏动指数（PI）、阻力指数（RI）下降，且研究组低于对照组（P<0.05）。两组移植后白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、白细胞介素-17（IL-17）、Th17细胞比例下降，且研究组低于对照组（P<0.05）。研究组的囊胚种植率、活产率、临床妊娠率高于对照组，生化妊娠率低于对照组（P<0.05），两组早期流产率组间对比无统计学差异（P>0.05）。结论：宫腔灌注HCG可有效改善RIF患者子宫内膜血流、Th17细胞水平以及妊娠结局，具有较好的临床应用价值。     

IL-6抗体对银屑病小鼠的治疗作用及其对外周血辅助性T细胞和树突状细胞影响的研究

摘要 目的：研究白介素-6（Interleukin-6,IL-6）抗体对银屑病小鼠的治疗作用,并探讨IL-6抗体治疗对银屑病小鼠外周血辅助性T细胞和树突状细胞影响。方法：30只6-8周龄SPF级BALB/c小鼠按照随机数字表法分为Normal组、Model组和IL-6组,Model组和IL-6组小鼠通过在背部脱毛区涂抹咪喹莫特建立银屑病小鼠模型。IL-6组小鼠通过在背部脱毛区皮下注射IL-6抗体进行治疗。比较三组小鼠皮损组织银屑病皮损面积及严重程度指数（psoriasis area and severity index,PASI）、表皮厚度和血管数、血清TNF-α、IL-17和IL-23含量、外周血树突状细胞、Th17细胞和Th22细胞比例以及皮损组织IL-6、IL-21和STAT3蛋白表达。结果：IL-6抗体治疗后,Model组和IL-6组小鼠皮损组织PASI、表皮厚度和血管数,血清TNF-α、IL-17和IL-23含量,外周血树突状细胞、Th17细胞和Th22细胞比例,以及皮损组织IL-6、IL-21和STAT3蛋白表达均显著高于Normal组小鼠（P<0.05）;与Model组相比,IL-6组小鼠皮损组织PASI、表皮厚度和血管数,血清TNF-α、IL-17和IL-23含量,外周血树突状细胞、Th17细胞和Th22细胞比例,以及皮损组织IL-6、IL-21和STAT3蛋白表达均显著降低（P<0.05）。结论：IL-6抗体对银屑病小鼠模型具有较好的治疗作用,其机制可能与通过抑制IL-6/STAT3通路影响Th17/Th22和树突状细胞水平有关。     

糖皮质激素联合利妥昔单抗对特发性膜性肾病患者血脂、Th17/Treg失衡和血清PLA2R抗体、THSD7A抗体的影响

摘要 目的：探讨糖皮质激素联合利妥昔单抗对特发性膜性肾病（IMN）患者血脂、辅助性T细胞17（Th17）/调节性T细胞（Treg）失衡和血清抗磷脂酶A2受体（PLA2R）抗体、抗I型血小板反应蛋白7A域（THSD7A）抗体的影响。方法：收集空军军医大学唐都医院2022年3月~2023年3月期间收治的IMN患者112例。根据随机数字表法将入组患者分为对照组（56例,糖皮质激素治疗）与治疗组（56例,对照组的基础上接受利妥昔单抗治疗）。观察两组疗效、血脂[低密度脂蛋白胆固醇（LDL-C）、总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）、甘油三酯（TG）]、肾功能[胱抑素C（CysC）、血肌酐（Scr）、血尿素氮（BUN）、24 h尿蛋白定量]、Th17/Treg相关指标[Th17细胞百分比、白细胞介素-17（IL-17）、Treg细胞百分比、转化生长因子β1（TGF-β1）、肿瘤坏死因子-α（TNF-α）]和血清PLA2R抗体、THSD7A抗体水平变化情况,并观察两组治疗安全性。结果：与对照组相比,治疗组的临床总有效率更高（P<0.05）。与对照组相比,治疗组治疗6个月后TC、TG、LDL-C、CysC、Scr、BUN、24 h尿蛋白定量、Th17、IL-17、TNF-α、PLA2R抗体、THSD7A抗体更低,HDL-C、Treg、TGF-β1更高（P<0.05）。两组不良反应发生率对比未见差异（P>0.05）。结论：糖皮质激素联合利妥昔单抗应用于IMN患者,可有效改善患者血脂、Th17/Treg失衡和血清PLA2R抗体、THSD7A抗体水平,且不增加不良反应发生率,具有较好的临床应用价值。     

大柴胡汤对轻症急性胰腺炎患者Th17/Treg免疫平衡和血清水通道蛋白的影响

摘要 目的：观察大柴胡汤对轻症急性胰腺炎（MAP）患者辅助性T细胞17 /调节性T细胞（Th17/Treg）免疫平衡和血清水通道蛋白（AQP）的影响。方法：按照随机数字表法，将天津中医药大学第一附属医院2020年4月~2022年4月期间收治的95例MAP患者分为对照组（西医基础治疗，47例）和研究组（对照组基础上接受大柴胡汤治疗，48例）。对比两组中医证候积分、Th17/Treg免疫平衡、AQP1、AQP5、AQP6和实验室指标。结果：两组治疗7 d后两胁胀痛，矢气则舒，右中上腹痛，恶心呕吐，抑郁易怒，嗳气呃逆，大便不畅评分均下降，且研究组低于对照组（P<0.05）。两组治疗7 d后Treg细胞比例升高，Th17细胞比例、Th17/Treg下降，且研究组的改善幅度大于对照组（P<0.05）。两组治疗7 d后AQP1、AQP5、AQP6升高，且研究组高于对照组（P<0.05）。两组治疗7 d后淀粉酶（AMY）、脂肪酶（LIP）、C反应蛋白（CRP）下降，且研究组低于对照组（P<0.05）。结论：大柴胡汤治疗MAP疗效确切，可以缓解患者的临床症状，有效改善MAP患者Th17/Treg免疫平衡和血清AQP1、AQP5、AQP6水平。     

慢性牙周炎患者血清CGRP、PGE2、CCL20与牙周临床指标和Th17/Treg失衡的相关性分析

摘要 目的：探究慢性牙周炎患者血清降钙素基因相关肽（CGRP）、前列腺素E₂（PGE₂）、CC趋化因子配体20（CCL20）与牙周临床指标和辅助性T淋巴细胞17/调节性T淋巴细胞（Th17/Treg）失衡的相关性。方法：选取2020年5月-2022年5月海南省妇女儿童医学中心收治的91例慢性牙周炎患者,根据其严重程度分为轻度组（39例）、中度组（36例）、重度组（16例）,比较三组血清CGRP、PGE₂、CCL20、牙周临床指标[出血指数（BI）、探诊深度（PD）、附着丧失（AL）、菌斑指数（PLI）]、外周血Th17细胞比例、Treg细胞比例、Th17/Treg比值,采用Pearson相关分析血清CGRP、PGE₂、CCL20与牙周临床指标和Th17/Treg失衡的相关性。结果：与轻度组比较,中度组、重度组血清CGRP、Treg细胞比例显著降低（P＜0.05）,血清PGE₂、CCL20、BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值显著增高（P＜0.05）;与中度组比较,重度组血清CGRP、Treg细胞比例显著降低（P＜0.05）,血清PGE₂、CCL20、BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值显著增高（P＜0.05）。相关性结果提示,血清PGE₂、CCL20水平与BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值呈正相关（P＜0.05）,与Treg细胞比例呈负相关（P＜0.05）;血清CGRP水平与BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值呈负相关（P＜0.05）,与Treg细胞比例呈正相关（P＜0.05）。结论：慢性牙周炎患者血清CGRP、PGE₂、CCL20水平与疾病严重程度、牙周临床指标及Th17/Treg失衡显著相关,血清CGRP、PGE₂、CCL20可能通过影响Th17/Treg平衡参与慢性牙周炎的发生和发展。     

枯草杆菌二联活菌肠溶胶囊联合泮托拉唑对UC患者炎性因子、肠黏膜功能及外周血Th17、CD4+CD25+Treg细胞表达的影响

摘要 目的：观察枯草杆菌二联活菌肠溶胶囊联合泮托拉唑对溃疡性结肠炎（UC）患者炎性因子、肠黏膜功能及外周血Th17、CD4⁺CD25⁺Treg细胞表达的影响。方法：研究对象选择2014年7月~2018年9月期间来我院香山路门诊部接受诊治的80例UC患者,随机分为联合组（枯草杆菌二联活菌肠溶胶囊联合泮托拉唑治疗）、对照组（泮托拉唑治疗）,各40例。对比两组的疗效、炎性因子、肠黏膜功能及外周血中Th17及CD4⁺CD25⁺Treg细胞表达 。记录两组治疗期间不良反应发生情况。结果：联合组的临床总有效率为92.50%（37/40）,对照组为70.00%（28/40）,两组比较差异有统计学意义（P<0.05）。两组不良反应发生率对比无差异（P>0.05）。联合组治疗6个月后血清白介素-8（IL-8）、肿瘤坏死因子-α（TNF-α）、C反应蛋白（CRP）水平均明显比对照组低（P<0.05）。联合组治疗6个月后血清D-乳酸含量、二胺氧化酶（DAO）水平均明显比对照组低（P<0.05）。联合组治疗6个月后外周血中Th17细胞表达比对照组低,CD4⁺CD25⁺Treg细胞表达比对照组高（P<0.05）。结论：枯草杆菌二联活菌肠溶胶囊联合泮托拉唑治疗UC患者,可有效改善肠道环境,使外周血中的 Th17 细胞表达降低,CD4⁺CD25⁺Treg细胞表达增加,并缓解炎症状态,临床效果满意且安全性好。     

Chiral separation and quantification of R/S-amphetamine, R/S-methamphetamine, R/S-MDA, R/S-MDMA, and R/S-MDEA in whole blood by GC-EI-MS

The enantioselective composition of the amphetamines is of interest, as the enantiomers show differences in their pharmacological effects and several methods for chiral separation of amphetamines have been described. Only a few methods have used whole blood as matrix and none of these separates both classic amphetamines (amphetamine and methamphetamine) and designer amphetamines (MDA, MDMA and MDEA). The aim of this study was, therefore, to develop a method for enantioselective analysis of AM, MA, MDA, MDMA, and MDEA in whole blood. The amphetamines were extracted from 0.5 g of whole blood by liquid-liquid extraction. After derivatization with R-MTPCl, the resulting diastereomers were separated by GC on a HP-5MS column and detected by SIM-MS. R-MTPCl was used as derivatization reagent because of the stability of this reagent and good separation of these analytes. Through the method, development time and temperature of the derivatization were optimized, and by admixture of 0.02% triethylamine it became possible to detect the amphetamines in adequately low concentrations as more analytes were derivatized. The method was validated and it was linear from 0.004 to 3 microg/g per enantiomer. The accuracy was within 91-115%, while the repeatability and reproducibility were < or =15% R.S.D. A method suitable for enantioselective separation and analysis of the amphetamines has been achieved, and the method was applied to analysis of whole blood samples originating from traffic and criminal cases and post mortem cases.     

Synthesis, characterization, cytotoxicity and antibacterial studies of chitosan, O-carboxymethyl and N,O-carboxymethyl chitosan nanoparticles

Chitosan (CS) is a naturally occurring biopolymer. It has important biological properties such as biocompatibility, antifungal and antibacterial activity, wound healing ability, anticancerous property, anticholesteremic properties, and immunoenhancing effect. Recently, CS nanoparticles have been used for biomedical applications. However, due to the limited solubility of CS in water its water-soluble derivatives are preferred for the above said applications. In this work, the nanoparticles of CS and its water-soluble derivatives such as O-carboxymethyl chitosan (O-CMC) and N,O-carboxymethyl chitosan (N,O-CMC) was synthesized and characterized. In addition, cytotoxicity and antibacterial activity of the prepared nanoparticles was also evaluated for biomedical applications.     

Cloning and expression of the Apa LI, Nsp I, Nsp HI, Sac I, Sca I, and Sap I restriction-modification systems in Escherichia coli

The genes encoding the ApaLI (5′-G^TGCAC-3′), NspI (5′-RCATG^Y-3′), NspHI (5′-RCATG^Y-3′), SacI (5′-GAGCT^C-3′), SapI (5′-GCTCTTCN1^-3′, 5′-^N4GAAGAGC-3′) and ScaI (5′-AGT^ACT-3′) restriction-modification systems have been cloned in E.␣coli. Amino acid sequence comparison of M.ApaLI, M.NspI, M.NspHI, and M.SacI with known methylases indicated that they contain the ten conserved motifs characteristic of C5 cytosine methylases. NspI and NspHI restriction-modification systems are highly homologous in amino acid sequence. The C-termini of the NspI and NlaIII (5′-CATG-3′) restriction endonucleases share significant similarity. 5mC modification of the internal C in a SacI site renders it resistant to SacI digestion. External 5mC modification of a SacI site has no effect on SacI digestion. N4mC modification of the second base in the sequence 5′-GCTCTTC-3′ blocks SapI digestion. N4mC modification of the other cytosines in the SapI site does not affect SapI digestion. N4mC modification of ScaI site blocks ScaI digetion. A DNA invertase homolog was found adjacent to the ApaLI restriction-modification system. A DNA transposase subunit homolog was found upstream of the SapI restriction endonuclease gene. Received: 15 April 1998 / Accepted: 3 August 1998     

Anthocyanins of Cephaelis, Cynomorium, Euterpe, Lavatera and Pinanga

The two malonylated pigments, malonylmalvin and malvidin 3-malonylglucoside, were identified in petals of Lavatera maritima, which belongs to the Malvaceae, a family known to synthesise such pigments. Zwitterionic anthocyanins could not be detected in four other newly examined sources and common unacylated pigments were recorded. Thus, the fruits of the palms Euterpe edulis and Pinanga polymorpha have a mixture of cyanidin 3-glucoside and cyanidin 3-rutinoside, while the fruit of Cephaelis subcoriacea is coloured by cyanidin 3-glucoside. The latter pigment was also obtained from the reddish brown inflorescence of the parasitic plant Cynomorium coccineum.     

Preparation, properties and crystal structure of two isomers of R,R,S,S- and R,S,R,S-[chloro(1,3,10,12,16,19-hexaazatetracyclo[17,3,1,1,0]tetracosane)copper(II)]

Two isomers (R,S,R,S- and R,R,S,S-) of five coordinate complex [Cu(L)Cl]⁺ have been separated and characterised. These two isomers have significantly different spectrochemical and electrochemical properties. Absorption maximum of R,S,R,S-[Cu(L)Cl]⁺ shifts to longer wavelength and its reduction potential shifts to more positive direction comparing those of R,R,S,S-[Cu(L)Cl]⁺. R,S,R,S-[Cu(L)Cl]⁺ is significantly distorted to trigonal-bipyramidal structure, whereas R,R,S,S-[Cu(L)Cl]⁺ retains almost square-planar geometry. The average bond distance of Cu-N in basal plane of R,S,R,S-[Cu(L)Cl]⁺ is longer by 0.024 Å than that of R,R,S,S-[Cu(L)Cl]⁺, whereas the bond distance of Cu-Cl in former is shorter by 0.200 Å than that in latter. The isolated square-planar complexes of R,R,S,S- and R,S,R,S-[Cu(L)](ClO₄)₂ are converted to the R,R,S,S- and R,S,R,S-[Cu(L)Cl]⁺ by the addition of Cl⁻ in nitromethane solution with the rate constants, k=1.70 (±0.02) and 8.31 (±0.07) M⁻¹ s⁻¹, respectively.     

Synthesis, characterization and redox behaviour of benzoyldiazenido- and oxorhenium complexes bearing N,N- and S,S-type ligands

The reactions of [ReCl₂{η²-N₂C(O)Ph}(PPh₃)₂] (1) with 2-aminopyrimidine (H₂Npyrm), 2,2′-bipyridine (bpy) and tetraethylthiuram disulfide (tds), in MeOH upon reflux, lead to the new η¹-(benzoyldiazenido)rhenium(III) complexes [ReCl{η¹-N₂C(O)Ph}(HNpyrm)(PPh₃)₂] (2) and [ReCl₂{η¹-N₂C(O)Ph}(bpy)(PPh₃)] (3), and the known oxo(diethyldithiocarbamato)dirhenium(v) complex [Re₂O₂(μ-O){Et₂NC(S)S}₄] (4), respectively. The Et₂NC(S)S ligands in 4 result from S-S bond rupture of tds molecules. The obtained compounds have been characterized by IR, ¹H, ³¹P{¹H} and ¹³C{¹H} NMR spectroscopies, FAB⁺-MS, elemental and single-crystal X-ray diffraction (for 2 and 4) analyses. Complex 2 represents the first structurally characterized Re compound derived from 2-aminopyrimidine. Besides, the redox behaviour of 2-4 in CH₂Cl₂ solution has been studied by cyclic voltammetry, and the Lever electrochemical ligand parameter (E_L) has been estimated, for the first time, for HNpyrm. The electrochemical results are discussed in terms of electronic properties of the Re centres and the ligands.     

Recent advances in the cryopreservation of shoot-derived germplasm of economically important fruit trees of Actinidia, Diospyros, Malus, Olea, Prunus, Pyrus and Vitis

This paper presents the advances made over the last decade in cryopreservation of economically important vegetatively propagated fruit trees. Cryopreservation protocols have been established using both dormant buds sampled on field-grown plants and shoot tips sampled on in vitro plantlets. In the case of dormant buds, scions are partially dehydrated by storage at − 5 °C, and then cooled slowly to − 30 °C using low cooling rates (c.a. 1 °C/h) before immersion in liquid nitrogen. After slow rewarming and rehydration of samples, regrowth takes place either through grafting of buds on rootstocks or excision of apices and inoculation in vitro. In the case of shoot tips of in vitro plantlets, the cryopreservation techniques employed are the following: controlled rate cooling procedures involving slow prefreezing followed by immersion in liquid nitrogen or vitrification-based procedures including encapsulation–dehydration, vitrification, encapsulation–vitrification and droplet-vitrification. The current status of cryopreservation for a series of fruit tree species including Actinidia, Diospyros, Malus, Olea, Prunus, Pyrus and Vitis is presented. Routine application of cryopreservation for long-term germplasm storage in genebanks is currently limited to apple and pear, for which large cryopreserved collections have been established at NCGRP, Fort Collins (USA), using dormant buds and in vitro shoot tips, respectively. However, there are a growing number of examples of pilot scale testing experiments under way for different species in various countries. Progress in the further development and application of cryopreservation techniques will be made through a better understanding of the mechanisms involved in the induction of tolerance to dehydration and cryopreservation in frozen explants.     

First records of flower biology and pollination in African Annonaceae: Isolona, Piptostigma, Uvariodendron, Monodora and Uvariopsis

Seven species from five genera of Annonaceae were studied with regard to their flower biology and pollination in the Southwest Province of Cameroon, West Africa. They have protogynous hermaphroditic flowers, with exception of Uvariopsis species, which are monoecious. Fused petals of Isolona campanulata remain apically spreading and open during anthesis but form a deep basal urceolate tube around the reproductive organs. At anthesis the yellow pendent flowers emit a fruit-like scent and attracted small beetles, the likely pollinators. Piptostigma sp. flowers also emit a fruit-like scent but provide a closed pollination chamber formed by the three inner petals. Small staphylinid beetles attracted during the female stage of anthesis are released from the flowers at the end of the male stage 2-3 days later. Both species have diurnal anthesis, attracting and releasing the flower visitors during daytime. In contrast, Uvariodendron connivens and U. calophyllum have nocturnal anthesis with floral thermogenesis, produce spicy, aromatic and fruity scents and attract large Scarabaeidae beetles, the pollinators, along with many curculionid beetles, which were principally predators of the thick petals. The very large flowers of Monodora tenuifolia have yellowish petals which are spotted with dark red markings. Together with the sweetish, slightly disagreeable scent the flowers attract flies, principally dung flies. The two investigated Uvariopsis species are monoecious with pistillate and staminate flowers being functional at the same time. The violet red flowers of U. bakeriana visually seem to mimic the fruiting body of certain stinkhorn fungi (Phallaceae) although without producing their strong unpleasant carcass stench. Flower-visiting dung flies were rare. Conversely, U. congolana has a strong fungus-like scent, its flowers are presented at litter height and dung flies living in the litter were the flower visitors, albeit sporadic. The 4-5 days lasting anthesis of both Uvariopsis species appears to be an evolutionary consequence of their diffuse pollinator spectra. The studied African Annonaceae therefore have either cantharophilous or myiophilous/sapromyiophilous flowers with, in part, respectively, remarkably long anthesis, thermogenesis, and widely open, large flowers - all attributes unknown or rare in the hitherto better studied Neotropical Annonaceae.     

Synthesis,Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.     

Purification, Characterization, and Crystallization of anN-HydroxyarylamineO-Acetyltransferase fromSalmonella typhimurium

TheN-hydroxyarylamineO-acetyltransferase fromSalmonella typhimuriumhas been expressed as a histidine-tagged fusion protein inEscherichia coliand purified to apparent homogeneity using single-step immobilized metal ion chromatography. Sufficient quantities of the purified protein have been obtained to allow its characterization by physical methods including dynamic light scattering and electrospray mass spectrometry. The substrate specificity and temperature sensitivity of the enzymatic activity have also been assessed. The enzyme has been crystallized from sodium, potassium tartrate and X-ray diffraction data have been obtained to allow the identification of an orthorhombic unit cell, point group P2₁2₁2, with dimensionsa= 137 Å,b= 223 Å, andc= 105 Å. These crystals will provide a route to a crystallographic determination of the structure of the protein.