来氟米特通过调节miR-449a在肺纤维化中的机制研究

目的 探究来氟米特（leflunomide,LEF）通过调节微小RNA（microRNA,miR）-449a在肺纤维化中的机制研究。方法 将人肺成纤维细胞MRC-5分为6组,即对照组、LEF组、LEF+mimic组、mimic组、LEF+inhibitor组和inhibitor组。通过质粒转染miR-449a mimic或inhibitor来过表达或沉默miR-449a,在5 mg/L LEF的条件下培养48 h。分别通过CCK-8法、克隆形成实验和流式细胞术检测各组细胞活力、细胞增殖能力和凋亡率。使用免疫荧光染色检测α平滑肌肌动蛋白（α smooth muscle actin,α-SMA）胶质蛋白I（collagen I,col I）。分别使用qPCR和Western blot检测miRNA和蛋白的水平。结果 mimic组miR-449a水平显著高于对照组（P<0.05）。LEF组和inhibitor组的miR-449a水平显著低于对照组（P<0.05）。LEF+mimic组的miR-449a的表达水平显著高于LEF组,LEF+inhibitor组的miR-449a水平显著低于LEF组（P<0.05）。LEF组和inhibitor组的细胞活力和细胞增殖能力显著高于对照组（P<0.05）。mimic组的细胞活力和细胞增殖能力显著低于对照组（P<0.05）。LEF+mimic组的细胞活力和细胞增殖能力显著低于LEF组而LEF+inhibitor组的细胞活力显著高于LEF组（P<0.05）。LEF组和inhibitor组的细胞凋亡率低于对照组（P<0.05）,mimic组的细胞凋亡率显著高于对照组（P<0.05）。LEF+mimic组的细胞凋亡率显著高于LEF组而LEF+inhibitor组的凋亡率显著低于LEF组（P<0.05）。LEF组和inhibitor组的α-SMA和Col I蛋白的荧光强度显著高于对照组（P<0.05）,mimic组的相对荧光强度低于对照组（P<0.05）。LEF+mimic组的α-SMA和Col I蛋白相对荧光强度显著低于LEF组,LEF+inhibitor组的α-SMA和Col I蛋白相对荧光强度显著高于LEF组（P<0.05）。LEF组和inhibitor组的p-JNK/JNK水平高于对照组（P<0.05）,mimic组的p-JNK/JNK水平显著低于对照组（P<0.05）,LEF+mimic组中p-JNK/JNK水平显著低于LEF组而LEF+inhibitor组的p-JNK/JNK水平显著高于LEF组（P<0.05）。结论 LEF可能通过抑制肺成纤维细胞中miR-449a的表达激活JNK途径,从而诱导成纤维细胞的活化和增殖,抑制其凋亡,从而引起肺纤维化。     

miR-1915-3p在胃癌细胞中的表达水平及其对胃癌细胞增殖和凋亡的影响

目的 检测miR-1915-3p在胃癌细胞中的表达水平,探讨其对胃癌细胞增殖和凋亡的影响。方法 实时定量聚合酶链反应（qRT-PCR）检测胃癌细胞MGC-803、SGC-7901、MKN-45和永生化胃上皮细胞GES-1中miR-1915-3p的相对表达水平;转染实验将miR-1915-3p质粒和对照质粒（miR-NC）转染至MGC-803和SGC-7901中,分别设置MGC-803细胞miR-1915-3p组和miR-NC组及SGC-7901细胞miR-1915-3p组和miR-NC组;细胞增殖实验和凋亡实验分别检测miR-1915-3p组和miR-NC组细胞的光密度（OD）值和凋亡率;蛋白免疫印迹（Western blot）实验检测miR-1915-3p组和miR-NC组细胞的Bcl-2蛋白表达情况。结果 MGC-803、SGC-7901、MKN-45细胞中miR-1915-3p的相对表达水平分别为（0.46±0.06）、（0.42±0.05）、（0.33±0.04）,均低于GES-1细胞中miR-1915-3p的相对表达水平（P<0.05）。MGC-803细胞中,miR-1915-3p组与miR-NC组相比,OD值降低、细胞凋亡率增加、Bcl-2蛋白表达减弱（P均<0.05）;SGC-7901细胞中,miR-1915-3p组与miR-NC组相比,OD值降低、细胞凋亡率增加、Bcl-2蛋白表达减弱（P均<0.05）。结论 miR-1915-3p在胃癌细胞系中表达降低,上调miR-1915-3p的表达可抑制胃癌细胞增殖,减弱Bcl-2蛋白表达以促进细胞凋亡。     

miR-125a-5p对卵巢癌细胞的增殖迁移和侵袭能力的影响

目的 探讨miR-125a-5p对卵巢癌细胞增殖、迁移和侵袭的影响及其作用的靶基因。方法 购入正常人卵巢上皮细胞HOSEpiC,卵巢癌细胞SKOV3、A2780、ES2和HO8910各1株,通过实时定量聚合酶链式反应（RT-PCR）检测人卵巢上皮细胞HOSEpiC以及卵巢癌细胞SKOV3、A2780、ES2和HO8910中miR-125a-5p的表达水平。利用生物信息学方法预测miR-125a-5p的靶基因,构建预测靶基因3’端非编码区（3’-UTR）的野生型（WT）和突变型（mut）荧光素酶报告基因质粒,通过双荧光素酶报告基因法验证miR-125a-5p与预测靶基因的靶向作用。利用慢病毒感染的方法建立稳定过表达miR-125a-5p的SKOV3细胞,使用荧光定量PCR和Western blot检测靶基因的表达水平。利用细胞计数试剂盒-8（CCK-8）分析过表达miR-125a-5p的SKOV3细胞增殖能力的变化,通过Transwell迁移和侵袭试验分析过表达miR-125a-5p的SKOV3细胞迁移和侵袭能力的变化。结果 正常人卵巢上皮细胞HOSEpiC中miR-125a-5p的表达水平高于卵巢癌细胞SKOV3、A2780、ES2和HO8910中miR-125a-5p的表达水平,其中SKOV3中miR-125a-5p的表达水平最低,差异均有统计学意义（P<0.05）,选择SKOV3进行后续实验。生物信息学分析显示,miR-125a-5p能够靶向结合Rab3D的3’-UTR;双荧光素酶报告基因分析证实miR-125a-5p能够靶向作用于Rab3D的3’-UTR。筛选稳定表达miR-125a-5p和si-Rab3D及相应对照的SKOV3细胞,分别命名为SKOV3/miR-125a-5p组,SKOV3/si-Rab3D组,SKOV3/miR-NC组和SKOV3/si-NC组。在SKOV3/miR-125a-5p组中,Rab3D的表达水平低于SKOV3组和SKOV3/miR-NC组,差异均有统计学意义（P<0.05）。细胞增殖能力检测结果显示,与SKOV3组和SKOV3/miR-NC组相比,SKOV3/miR-125a-5p组在72小时和96小时细胞增殖能力降低,差异有统计学意义（P<0.05）。Transwell迁移和侵袭试验结果显示,SKOV3/miR-125a-5p组分别与SKOV3组和SKOV3/miR-NC组相比,细胞迁移和侵袭能力均显著下降,差异有统计学意义（P<0.05）。结论 miR-125a-5p能够靶向作用Rab3D,抑制卵巢癌细胞的增殖、迁移和侵袭。     

circ_0000264促进乳腺癌细胞增殖、迁移和侵袭

目的 探讨环状RNA circ_0000264在乳腺癌细胞增殖、迁移和侵袭中的功能及作用机制。方法 采用qRT-PCR检测乳腺癌组织和细胞系中circ_0000264的表达;利用si-circ_0000264构建敲低circ_000026的细胞模型;分别采用CCK-8、BrdU和Transwell实验检测细胞的增殖、迁移和侵袭;采用双荧光素酶报告基因实验验证circ_0000264与miR-622的靶向调控关系。结果 circ_0000264在乳腺癌组织和细胞中均呈高表达（P<0.05）。与对照组相比,敲低circ_0000264可抑制乳腺癌细胞的增殖、迁移和侵袭（P<0.05）。circ_0000264对miR-622具有吸附作用。下调miR-622可部分逆转敲低circ_0000264对乳腺癌细胞增殖和转移的抑制作用。结论 circ_0000264在乳腺癌进展过程中发挥促进作用;circ_0000264通过负向调控miR-622促进乳腺癌细胞的增殖、迁移和侵袭。     

circ-LRP6调控miR-515-5p/IL-6通路影响卵巢癌细胞增殖、迁移和侵袭

目的 探讨环状RNA低密度脂蛋白受体相关蛋白6（circ-LRP6）对卵巢癌细胞增殖、迁移和侵袭的影响及其分子机制。方法 选取44例卵巢癌患者的癌组织及癌旁组织,培养正常人卵巢上皮细胞HUM-CELL-0088及卵巢癌细胞系SKOV3、OVCAR3、A2780,采用实时荧光定量PCR检测卵巢癌组织和细胞中circ-LRP6、微小RNA-515-5p（miR-515-5p）的表达水平;双荧光素酶报告实验检测miR-515-5p与circ-LRP6之间的靶向关系;将circ-LRP6干扰表达载体、miR-515-5p过表达载体、miR-515-5p抑制表达载体与circ-LRP6干扰表达载体转染至卵巢癌细胞SKOV3中,蛋白质印迹法（Western blotting）检测细胞周期蛋白D1（Cyclin D1）、基质金属蛋白酶（MMP）2、MMP9、白细胞介素6受体（IL-6R）蛋白的表达;CCK-8法检测SKOV3细胞活性;Transwell小室法检测细胞迁移和侵袭。结果 与癌旁组织及HUM-CELL-0088细胞相比,卵巢癌组织和SKOV3、OVCAR3、A2780细胞系中circ-LRP6表达水平显著升高,miR-515-5p表达水平显著降低（P<0.05）。双荧光素酶报告实验证实circ-LRP6可靶向负调控miR-515-5p的表达。低表达circ-LRP6或过表达miR-515-5p均可抑制Cyclin D1、MMP2、MMP9、IL-6R的表达,降低细胞活性,抑制细胞迁移和侵袭（P<0.05）。同时,抑制circ-LRP6和miR-515-5p表达可上调SKOV3细胞中Cyclin D1、MMP2、MMP9、IL-6R的表达,增强细胞活性,促进细胞迁移和侵袭（P<0.05）。结论 抑制circ-LRP6表达可能通过上调miR-515-5p抑制IL-6,从而抑制卵巢癌SKOV3细胞的增殖、迁移和侵袭。     

miR-578调控长链脂酰辅酶A合成酶4表达对胃癌细胞增殖、侵袭的影响

目的 探讨miR-578调控长链脂酰辅酶A合成酶4（ACSL4）对胃癌细胞增殖及侵袭的影响。方法 选取人胃癌细胞MKN-45、SNU-1、MKN-7、KTAO3、N87及人正常胃黏膜细胞GES-1为研究对象,将MKN-45细胞分为对照组、miR-578 NC组、miR-578 mimic组、miR-578 mimic+pc-ACSL4组,测定各组MKN-45细胞活力及凋亡、侵袭、迁移能力,测定细胞中miR-578、ACSL4、凋亡相关蛋白（Bax、Caspase-3、Bcl-2）、侵袭相关蛋白（MMP-9、MMP-2）的表达,验证miR-578与ACSL4的靶向关系。结果 miR-578在人胃癌细胞中低表达;与对照组相比,miR-578 mimic组MKN-45细胞活力、侵袭、迁移能力、MMP-2、MMP-9、Bcl-2蛋白表达水平均显著降低（P<0.05）,凋亡能力、Caspase-3、Bax蛋白表达水平均显著升高（P<0.05）;与miR-578 mimic组相比,miR-578 mimic+pc-ACSL4组MKN-45细胞活力、侵袭、迁移能力、MMP-2、MMP-9、Bcl-2蛋白表达水平均显著升高（P<0.05）,凋亡能力、Caspase-3、Bax蛋白表达水平均显著降低（P<0.05）;荧光素酶实验结果显示,miR-578与ACSL4存在靶向调节关系。结论 miR-578可抑制人胃癌细胞MKN-45的增殖及迁移能力,可能是通过抑制ACSL4表达实现的。     

黄芩苷联合奥沙利铂调控miR-433-3p/SRC对胃癌细胞增殖和侵袭的影响

目的 探究黄芩苷联合奥沙利铂调控miR-433-3p/SRC对胃癌细胞增殖和侵袭的影响。方法 将SGC-7901细胞分为对照组、黄芩苷（100、200、300 μmol·L^-1）组、奥沙利铂（33 μmol·L^-1）组,联合用药（300 μmol·L^-1黄芩苷+33 μmol·L^-1奥沙利铂）组,miR-433-3p组、miR-NC组、anti-miR-433-3p组、anti-miR-NC组、pcDNA-SRC组、si-SRC组,miR-433-3p+联合用药组、anti-miR-433-3p+联合用药组、pcDNA-SRC+联合用药组、si-SRC+联合用药组、miR-433-3p+pcDNASRC+联合用药组。CCK-8检测细胞增殖能力;Transwell小室法检测细胞侵袭能力;流式细胞仪检测细胞凋亡率;实时荧光定量PCR （qRT-PCR）检测细胞中miR-433-3p表达;双荧光素酶报告检测miR-433-3p和SRC的靶向关系;Westernblotting检测细胞中SRC蛋白表达。结果 与对照组相比,黄芩苷（100、200、300 μmol·L^-1）组、奥沙利铂组、联合用药组细胞增殖抑制率、凋亡率和miR-433-3p表达显著增加（P<0.05）,细胞侵袭数目、SRC蛋白表达显著减少（P<0.05）;与黄芩苷300 μmol·L^-1组、奥沙利铂组相比,联合用药组细胞增殖抑制率、凋亡率显著增加,细胞侵袭数目显著减少;与黄芩苷300 μmol·L^-1组比较,miR-433-3p表达显著增加（P<0.05）;与奥沙利铂组比较,SRC蛋白表达显著减少（P<0.05）。与对照组比较,miR-433-3p组细胞中miR-433-3p表达显著升高,SRC蛋白表达显著降低,anti-miR-433-3p组细胞中miR-433-3p表达显著降低,SRC蛋白表达显著升高（P<0.05）;miR-433-3p+联合用药组细胞增殖抑制率和凋亡率显著高于联合用药组,细胞侵袭数目显著少于联合用药组（P<0.05）,anti-miR-433-3p+联合用药组细胞增殖抑制率和凋亡率显著低于联合用药组,细胞侵袭数目显著多于联合用药组（P<0.05）。miR-433-3p组SRC-WT荧光素酶活性显著低于miR-NC组（P<0.05）。si-SRC组细胞中SRC蛋白表达显著低于对照组（P<0.05）,pcDNA-SRC组细胞中SRC蛋白表达显著高于对照组（P<0.05）;与pcDNA-SRC组相比,miR-433-3p+pcDNA-SRC组细胞中SRC蛋白表达显著降低（P<0.05）。si-SRC+联合用药组细胞增殖抑制率和凋亡率显著高于联合用药组,细胞侵袭数目显著少于联合用药组（P<0.05）,pcDNA-SRC+联合用药组细胞增殖抑制率和凋亡率显著低于联合用药组,细胞侵袭数显著高于联合用药组（P<0.05）。与pcDNA-SRC+联合用药组相比,miR-433-3p+pcDNA-SRC+联合用药组细胞增殖抑制率和凋亡率显著降低（P<0.05）,细胞侵袭数目显著升高（P<0.05）。结论 黄芩苷联合奥沙利铂可通过miR-433-3p靶向调控SRC抑制胃癌细胞的增殖和侵袭,诱导胃癌细胞凋亡。     

hsa-miRNA-30a-5p促进肺癌细胞A549增殖的机制研究

目的 研究hsa-miRNA-30a-5p促进肺癌细胞A549增殖的调控机制。方法 收集临床肺癌标本及癌旁组织5对,用荧光定量法（real time-PCR）和蛋白质印迹法（Western blotting）分别检测肿瘤及其癌旁组织中hsa-miRNA-30a-5p和SCARA5的蛋白含量;生物信息学预测hsa-miRNA-30a-5p与SCARA5基因3''UTR区结合位点,并通过荧光素酶报告基因法进行结合位点验证;构建SCARA5基因沉默表达载体pshRNA-SCARA5,脂质体瞬时转染pshRNA-SCARA5及hsa-miRNA-30a-5p阻遏物（miRNA-30a-5p inhibitor）到A549细胞,转染后48 h,real time-PCR检测细胞内hsa-miRNA-30a-5p含量,Western blotting检测细胞中SCARA5蛋白含量;MTT法检测转染后A549细胞对数期增殖活性。结果 肺癌组织中SCARA5蛋白表达量明显低于癌旁组织,组间差异显著（P<0.05）;肺癌组织中hsa-miRNA-30a-5p含量则明显高于癌旁组织,组间差异显著（P<0.05）。荧光素酶实验显示,与报告基因表达载体单独转染组比较,miRNA-30a拟似物（miRNA-30a-5p mimics）和miRNA-30a-5p inhibitor与野生型荧光素酶报告基因共转染组可以明显抑制或增强荧光素酶活性（P<0.05）;miRNA-30a-5p inhibitor转染细胞后48 h,与转染对照组比较,细胞内hsa-miRNA-30a-5p含量明显降低（P<0.05）,阴性对照（miRNA-30a-5p NC）转染组和转染对照组细胞内hsa-miRNA-30a-5p含量无显著差异（P>0.05）。转染后24~72 h,miRNA-30a-5p inhibitor转染组A549细胞增值活性明显降低（P<0.05）,而pshRNA-SCARA5转染能够逆转miRNA-30a-5p inhibitor增强A549细胞增殖活性的趋势,共转染组与miRNA-30a-5p inhibitor单独转染组及转染对照组比较,差异有统计学意义（P<0.05）。结论 Hsa-miRNA-30a-5p通过抑制SCARA5基因表达,增强A549细胞的增殖活性,转染miRNA-30a-5p inhibitor,可以抑制A549细胞增殖活性。     

EHD2与HER-2阳性乳腺癌细胞曲妥珠单抗敏感性的关系及作用机制

目的 研究EH结构域蛋白2（EHD2）对HER-2阳性乳腺癌细胞曲妥珠单抗（TZB）敏感性的影响及作用机制。方法 联合分析GEO、Kaplan-Meier plotter及TCGA数据库,筛选出与乳腺癌细胞TZB敏感性密切相关的基因EHD2。体外培养人乳腺癌细胞BT474,将其分为敏感组、抵抗组及干扰组,敏感组用PBS处理12周后转染PX459-Control载体,抵抗组用0.5、1、2、4、8、16 μg·mL^-1 TZB诱导12周后转染PX459-Control载体,干扰组用0.5、1、2、4、8、16 μg·mL^-1 TZB诱导12周后转染PX459-sgEHD2载体。CCK-8实验检测细胞的TZB半抑制浓度（IC₅₀）,实时荧光定量PCR及蛋白质印迹法检测EHD2及其潜在下游基因血小板源性生长因子β受体（PDGFRβ）的表达。结果 GEO数据库显示,EHD2在TZB抵抗的乳腺癌细胞中表达显著上调（P<0.05）;Kaplan-Meier plotter数据库分析发现,EHD2高表达与HER-2阳性乳腺癌患者预后不良显著相关（P<0.05）,与HER-2阴性乳腺癌患者生存时间延长显著相关（P<0.05）;TCGA数据库分析显示,乳腺癌组织中EHD2与PDGFRβ表达水平呈正相关（P<0.01）。与敏感组比较,抵抗组与干扰组TZB的IC₅₀显著升高,抵抗组EHD2、PDGFRβ的表达均显著上调,干扰组EHD2表达显著下调,PDGFRβ表达显著上调,差异均有统计学意义（P<0.05）;与抵抗组比较,干扰组TZB的IC₅₀显著降低,EHD2、PDGFRβ的表达均显著下调,差异有统计学意义（P<0.05）。结论 EHD2可促进HER-2阳性乳腺癌细胞的TZB抵抗,其机制可能与上调PDGFRβ表达有关。     

miR-197在人口腔鳞状细胞癌中的表达及对细胞增殖的作用机制★

目的 探讨miR-197在人口腔鳞状细胞癌（OSCC）中的表达及对细胞增殖的作用机制。方法 选取2015年3月—2019年3月在海南医学院第一附属医院选择手术切除病灶的100例OSCC患者的肿瘤组织及癌旁组织（距离病灶边缘超过2.5 cm），qRT-PCR检测miR-197在OSCC组织及细胞系CAL27中的表达，Western blotting检测JAK2在OSCC组织及细胞系中的表达。构建沉默miR-197表达的病毒载体（miR-197-siRNA）及miR-197-siRNA阴性对照（miR-197-siRNA-NC），转染CAL27细胞，以未处理的CAL27细胞作为空白对照；倒置显微镜观察转染miRNA-197后的细胞形态；流式细胞术、EdU标记实验、Transwell小室实验分别检测miR-197对CAL27细胞凋亡率、DNA合成能力、侵袭能力的影响；荧光素酶实验基因报告分析miR-197与JAK2的作用关系，Western blotting检测各组细胞中JAK2的表达。结果 qRT-PCR结果显示，与癌旁组织相比，miR-197在OSCC组织中的表达明显升高，JAK2在OSCC组织中的表达明显降低（P<0.05）。与人正常口腔黏膜角化细胞株HOKs相比，miR-197在人OSCC细胞株CAL27中的表达明显上升，JAK2在CAL27中的表达明显下降（P<0.05）；与miR-197-siRNA-NC组相比，miR-197-siRNA组贴壁细胞数量明显减少，胞质空泡样，细胞堆积明显增多，染色质固缩，核膜破损严重，线粒体空泡。流式细胞术、EdU标记实验、平板集落克隆实验、软琼脂集落形成实验结果表明，与miR-197-siRNA-NC组相比，miR-197-siRNA组细胞凋亡率明显增加，细胞内DNA合成明显受阻，细胞增殖和侵袭明显受到抑制，差异均具有统计学意义（P<0.05）；荧光素酶实验基因报告分析结果证明，miR-197与JAK2具有靶向调控关系；Western blotting结果表明，与miR-197-siRNA-NC组相比，miR-197-siRNA组细胞中JAK2的表达明显升高（P<0.05）。结论 miR-197在OSCC中呈高表达，下调miR-197可抑制OSCC细胞增殖，这可能与JAK信号通路有关。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.