老年心功能不全患者血清地高辛样免疫活性物质测定

采用荧光极化免疫分析法,检测了15例老年心功能不全病人血清地高辛样免疫活性物质(DLIS)浓度。以TDx仪最低检测限0.256nmol·L^-1为阳性检测标准,DLIS检出阳性率为46.7%(7/15),浓度范围0.26～1.52nmol·L^-1,平均浓度0.55±0.44nmol·L^-1;其中1例病人血清DLIS浓度高达1.52nmol·L^-1。结果表明老年心功能不全患者血清中含有较高水平的DLIS;提示对这些患者若因病情需要而用地高辛治疗时,其后的血浓度测定结果易引起“过高估计”,应当谨慎地评价地高辛血浓度测定结果。     

高效液相色谱法测定人血清和尿中盐酸青藤碱浓度及药代动力学研究

用RP-HPLC法,以三唑仑为内标,反相C₁₈为分析柱,乙腈—0.01mol·L^-1磷酸二氢钠—四甲基乙二胺(46∶54∶0.22v/v)为流动相,磷酸调至pH6.9,检测波长263nm,测定血清和尿中盐酸青藤碱浓度,线性范围分别为6～480ng·mL^-1和0.06～3μg·mL^-1,平均回收率75.88%和91.35%,日内日间误差小于5%,最低检测浓度血清4ng·mL^-1,尿40ng·mL^-1。8名健康男性志愿者单次口服盐酸青藤碱片80mg,测定血清及尿浓度,该药符合二室开放模型,体内消除符合一级动力学消除过程,主要药代动力学参数:T_1/2α0.791±0.491h,T_1/2β9.397±2.425h,T_{max 1.040±0.274h,Cmax246.604±71.165ng·mL^-1,AUC 2651.158±1039.050ng·h·mL^-1,CL 0.033±0.01ng·mL^-1。}     

高效毛细管电泳法研究盐酸班布特罗国产胶囊与进口片剂的人体生物等效性高效毛细管电泳法研究盐酸班布特罗国产胶囊与进口片剂的人体生物等效性

目的研究国产盐酸班布特罗胶囊和进口片剂的人体生物等效性。方法采用高效毛细管电泳法测定血浆中班布特罗及其代谢物特布他林的浓度。结果单次口服国产班布特罗胶囊和进口班布特罗片剂后班布特罗的药代动力学参数:AUC0-t分别为(71±18)和(72±13) μg·h·L^-1,实测C_max分别为(8.1±1.8)和(9.2±2.3) μg·L^-1,实测t_max分别为(3.6±1.3)和(3.7±1.0) h。特布他林药代动力学参数:AUC0-t分别为(129±33)和(130±34) μg·h·L^-1,实测C_max分别为(7.8±2.3)和(8.5±2.9) μg·L^-1,实测t_max分别为(5.4±0.8)和(5.6±1.1) h,国产班布特罗胶囊单次给药后的相对生物利用度为(100±16)%(班布特罗),(101±13)%(特布他林)。结论经统计学证明两制剂具有生物等效性。     

西红花苷对牛主动脉平滑肌细胞内钙离子浓度的影响

目的研究西红花苷对血管平滑肌细胞内钙离子浓度的影响。方法以Fluo-3/AM作为Ca²⁺荧光探针,采用激光扫描共聚焦显微镜观察牛主动脉平滑肌细胞内钙离子浓度的变化。结果无论细胞外有无钙离子,西红花苷(1×10^-8,1×10^-7,1×10^-6 mol·L^-1)均能明显抑制1×10^-2 mol·L^-1 H₂O₂引起的细胞内钙离子浓度的升高,其抑制率含钙条件下分别为34.1%, 57.1%和74.3%(P<0.01),无钙条件下分别为26.2%,32.1%和50.0%(P<0.01);在胞外无钙的条件下,西红花苷 (1×10^-8,1×10^-7,1×10^-6 mol·L^-1)能抑制70 mmol·L^-1 CHCl₃导致雷洛丁敏感钙池的释放,其抑制率分别为27.8%, 27.8%和50.0% (P<0.01)。结论西红花苷能抑制胞外钙离子的内流及内质网上钙离子的释放。     

喹诺酮类药物对茶碱药代动力学的影响

目的探讨喹诺酮类药物对茶碱药代动力学是否存在显著影响,为临床合理用药提供参考。方法采用自身对照法,测定家兔iv 10mg·kg^-1茶碱及每天1次灌服喹诺酮类药物,连续6d,再iv 10mg·kg^-1茶碱后血浆中茶碱浓度,计算药动学参数。结果合用氟罗沙星前后茶碱在家兔体内按一室模型处理。合用前后茶碱的的药动学参数分别为,K:0.154±0.035h^-1,0.151±0.044 h^-1;T_1/2:4.70±1.12 h,4.90±1.38 h;V:0.562±0.180 L·kg^-1,0.556±0.166 L·kg^-1;AUC_0～10:93.70±32.87 mg·h·L^-1,100.20±43.11 mg·h·L^-1;AUC_0～∞:147.87±68.08 mg·h·L^-1,157.16±80.69 mg·h·L^-1;CL:0.090±0.046 L·kg^-1·h^-1,0.091±0.052 L·kg^-1·h^-1;Cmax:19.91±5.25 mg·L^-1,20.12±5.24 mg·L^-1。以上合参数均无显著性差异(P>0.05)。合用氟罗沙星后茶碱的血浆浓度有一定波动,但无统计学意义(P>0.05)。合用芦氟沙星前后茶碱在家兔体内呈一室模型。茶碱的药动学参数分别为,K:0.147±0.017 h^-1,0.148±0.018 h^-1;T_1/2:4.76±0.54 h,4.74±0.56 h;V:0.581±0.089 L·kg^-1,0.555±0.075 L·kg^-1;AUC_0～10:91.42±11.14 mg·h·L^-1,94.97±10.20mg·h·L^-1;AUC_0～∞:119.48±14.96 mg·h·L^-1,124.05±14.76 mg·h·L^-1;CL:0.085±0.011 L·kg^-1·h^-1,0.082±0.010L·kg^-1·h^-1;Cmax:18.48±2.53 mg·L^-1,19.16±2.34mg·L^-1。合用芦氟沙星前后茶碱各参数均无显著性差异(P>0.05)。合用芦氟沙星后茶碱的血浆浓度有升高趋势,但无统计学意义(P>0.05)。合用培氟沙星前后茶碱在家兔体内呈一室模型。茶碱的药动学参数分别为,K:0.150±0.038 h^-1,0.110±0.018 h^-1,P<0.01;T_1/2:4.95±1.67 h,6.69±2.01 h,P<0.01;V:0.584±0.149 L·kg^-1,0.511±0.126 L·kg^-1,P<0.05;AΜC_0～10:97.71±40.09 mg·h·L^-1,126.11±42.72 mg·h·L^-1,P<0.01;AΜC_0～∞:136.05±83.40 mg·h·L^-1,202.10±99.81 mg·h·L^-1,P<0.01;CL:0.091±0.038 L·kg^-1·h^-1,0.056±0.018 L·kg^-1·h^-1,P<0.01;Cmax:18.94±4.89 mg·L^-1,21.82±5.40 mg·L^-1,P<0.05。合用加替沙星前后茶碱在家兔体内按一室模型处理。合用前后茶碱的药动学参数分别为,K:0.147±0.035 h^-1,0.127±0.026 h^-1;T_1/2:4.89±0.98 h,5.62±1.09h;V:0.541±0.162 L·kg^-1,0.538±0.154 L·kg^-1;AΜC_0～10:97.81±29.87 mg·h·L^-1,107.27±39.54mg·h·L^-1;AΜC_0～∞:153.32±65.64 mg·h·L^-1,174.01±71.03 mg·h·L^-1;CL:0.081±0.034 mg·h·L^-1,0.074±0.033 L·kg^-1·h^-1;Cmax:20.51±5.12 mg·L^-1,20.60±5.05 mg·L^-1。合用加替沙星前后茶碱各参数除T_1/2(P<0.05)外无显著差异。结论氟罗沙星、芦氟沙星对茶碱的血药浓度及药代动学参数没有显著影响;培氟沙星对茶碱的血药浓度及药代动学参数有显著影响;加替沙星对茶碱的血药浓度及除T_1/2的药代动学参数没有显著影响。     

HPLC/MS研究国产盐酸班布特罗片及其代谢物特布他林人体生物等效性

目的研究国产班布特罗片剂和进口片剂进行人体生物等效性研究。方法20名健康受试者随机交叉给药,用液相色谱/质谱联用测定血浆中班布特罗其代谢物特布他林的浓度。结果经数据处理,单次口服国产和进口班布特罗片剂后班布特罗的药代动力学参数:AUC_0-t分别为(52±21)μg·h·L^-1和(51±20)μg·h·L^-1,T_max分别为(2.9±0.9)h和(2.6±0.7)h,C_max分别为(6.0±2.6)μg·L^-1和(6.2±2.9)μg·L^-1。特布他林:AUC_0-t分别为(191±30)μg·h·L^-1和(197±37)μg·h·L^-1,T_max分别为(4.2±1.0)h和(4.2±1.0)h,C_max分别为(10±5)μg·L^-1和(10±4)μg·L^-1。国产班布特罗片剂单次给药后的相对生物利用度为102%±8%(班布特罗),100%±12%(特布他林)。结论经统计学证明两制剂有生物等效性。     

LC-MS/MS法测定人血浆中辛伐他汀的浓度及相对生物利用度

目的 建立人体血浆中辛伐他汀的LC-MS/MS测定方法,研究辛伐他汀片在男性健康志愿者体内的药代动力学行为,评价其生物利用度和生物等效性。方法 20名健康成年男性志愿者采用随机分组自身交叉对照试验设计,单剂量口服辛伐他汀片40 mg后,用LC-MS/MS联用法测定血浆中药物浓度。结果 试验制剂和参比制剂的主要药代动力学参数:t_max分别为(1.8±1.3)h和(2.10±1.00)h;c_max分别为(7.12±1.61)μg·L^-1和(7.38±1.54)μg·L^-1;AUC_(0-24)分别为(30.50±11.25)μg·L^-1·h^-1和(30.17±10.21)μg·L^-1·h^-1;t_1/2分别为(3.90±0.78)h和(3.76±0.85)h。以AUC_(0-24)计算的试验制剂的相对生物利用度为101.2%±7.8%。结论 建立的分析方法准确灵敏,测得的数据可靠,统计学分析表明两种制剂生物等效。     

非手性与手性色谱法研究尼莫地平及其对映体在大鼠体内的药代动力学及组织分布

目的研究尼莫地平及其对映体在大鼠体内药代动力学及组织分布特性。方法生物样品在碱性条件下,经正己烷-醋酸乙酯(1∶1)提取。非手性色谱分析用ODS柱(150 mm×4.6 mm ID),以甲醇-水(70∶30)为流动相;手性色谱分析用Chiralcel OJ柱(250 mm × 4.6 mm ID),以正己烷-无水乙醇(85∶15)为流动相;检测波长为236 nm。结果尼莫地平及其对映体分别在非手性及手性色谱系统中分离良好,在血浆及组织匀浆液中线性关系、最低检测限、精密度和准确度均满足分析要求。对映体间主要药动学参数T_max,C_max,AUC和CL_s,S-(-)-尼莫地平为:(2.1±0.3) h,(197±5) μg·L^-1,(656±18) μg·h·L^-1和(0.30±0.03) mL·min^-1,r-(+)-尼莫地平为:(1.7±0.5) h,(128±4)μg·L^-1,(381±8) μg·h·L^-1和(0.53±0.03) mL·min^-1;在主要的效应器官中S-(-)-尼莫地平的浓度高于r-(+)-尼莫地平,在主要消除器官中r-(+)-尼莫地平浓度高于S-(-)-尼莫地平的浓度。结论尼莫地平对映体在大鼠体内药代动力学及组织分布存在着立体差异性。     

替硝唑片在健康人体的药代动力学和相对生物利用度

目的 研究替硝唑片在健康人体的药代动力学和相对生物利用度。方法 采用高效液相色谱法测定20名健康男性志愿者,随机交叉单剂量口服替硝唑片1g后血浆中的药物浓度,计算药代动力学参数和相对生物利用度,并进行生物等效性评价。结果 受试和参比替硝唑片的t_1/2分别为(13.98±1.55)h、(13.80±0.93)h,t_max分别为(2.1±1.0)h、(2.3±0.9)h,c_max分别为(18.60±2.27)mg·L^-1、(18.47±3.14)mg·L^-1,AUC_0-τ分别为(368.49±44.08)mg·L^-1·h^-1、(353.86±40.99)mg·L^-1·h^-1。受试制剂于参比制剂的人体相对生物利用度为104.9±13.4%。结论 两种制剂的药代动力学参数相近,具有生物等效性。     

血清脂联素水平与冠状动脉粥样硬化程度的相关性

目的 探讨人血清脂联素水平与冠状动脉粥样硬化程度的关系。方法 根据冠状动脉造影结果和临床表现,将162例疑诊冠心病患者进行分组,用放射免疫法检测血清脂联素水平,同时测定患者血压、血脂、血糖等相关指标。结果 确诊冠心病患者血清脂联素水平(17.21±10.67 mg·L^-1)明显低于阴性对照组(32.94±15.18 mg·L^-1,P<0.01),脂联素水平随着动脉粥样硬化程度的加重呈进行性下降。血清脂联素水平与冠状动脉的狭窄程度、总胆固醇、甘油三酯、低密度脂蛋白胆固醇成负相关(P<0.01),与高密度脂蛋白胆固醇呈正相关(P<0.05)。结论 血清脂联素水平随动脉粥样硬化的发展呈进行性下降,有助于临床评价冠心病病变程度及其进展。     

Digoxin-like immunoreactive substance in renal transplant patients.

Digoxin-like immunoreactive substance (DLIS) has been detected in several patient populations that were not receiving digoxin, including those patients with end-stage renal disease. The structure and physiologic significance of this compound are unknown, and the fate of DLIS after renal transplantation has not been studied. The authors prospectively evaluated 163 patients (not receiving digoxin) before and after transplantation for the presence of DLIS. Three different assays were used: radioimmunoassay (RIA), affinity mediated immunoassay (ACA), and fluorescence polarization immunoassay (TDX I). Depending on the assay method used, 11% (RIA), 6% (ACA), and 9% (TDX) of patients had detectable DLIS pretransplant. Using all 3 assays, a total of 34 patients (21%) were found to have DLIS. The mean serum digoxin concentration was 0.41 +/- 0.13 ng/mL (range: 0.2-1.2 ng/mL) and DLIS was detectable by greater than 1 assay method in seven patients. DLIS persisted longer in patients who had delayed allograft function (13.7 +/- 7 days) than in those who did not (3 +/- 1.9 days), P less than .05. In summary, detection of DLIS in renal transplant recipients appears to be an infrequent occurrence when using a single digoxin assay method. When detected, the concentration of DLIS is often below the usual therapeutic range for digoxin and disappears once allograft function is established. The authors conclude that the presence of DLIS is unlikely to be clinically significant in the renal transplant population.     

Endogenous digoxin-like immunoreactivity in elderly patients with normal serum creatinine concentrations

The effect of digoxin-like immunoreactive substance (DLIS) on serum digoxin determinations in elderly patients with normal serum creatinine concentrations was studied. Patients in the study group were over 70 years of age; the control population was under 55 years of age. All patients had serum creatinine concentrations of less than or equal to 1.5 mg/dL. Apparent digoxin content of serum samples from patients receiving digoxin and from patients in each age group who were not receiving digoxin was determined in duplicate by each of two radioimmunoassays: RIANEN (New England Nuclear), which detects DLIS, and Immophase (Corning Medical and Scientific), which is far less cross-reactive with DLIS. Results from the patients under 55 years of age were analyzed for inherent bias between the assay methods. In patients over 70 years of age, concentrations of DLIS (differences between serum digoxin concentrations measured by RIANEN and Immophase) were compared with creatinine clearance values. No DLIS was detected in sera of patients who had not received digoxin. For patients who received digoxin, nearly all apparent digoxin concentrations were within the usual therapeutic range. For patients without liver or renal failure who received digoxin, no significant difference in digoxin concentrations was observed between the RIANEN and Immophase assays in either the young (n = 17) or elderly (n = 26) patients. There was no significant increase in the difference between the RIANEN and Immophase results with decreasing creatinine clearance. In the elderly patients with normal serum creatinine concentrations, there was no evidence that measurement of serum digoxin concentration using the RIANEN and Immophase assays was compromised by DLIS.     

Interaction between digoxin and indomethacin or ibuprofen.

To study a potential interaction between digoxin and two non-steroid anti-inflammatory drugs, indomethacin (50 mg three times daily) and ibuprofen (600 mg three times daily) were given for 10 days to 10 and 8 patients, respectively, on chronic digoxin treatment. Serum digoxin measured by fluorescence polarisation immunoassay increased significantly (P less than 0.05) during treatment with indomethacin from pre-treatment values of 0.73 +/- 0.34 nmol l-1 (mean +/- s.d.) to a mean value of 1.02 +/- 0.43 nmol l-1, while administration of ibuprofen did not change the steady state serum concentration of digoxin. The result demonstrates that some non-steroidal anti-inflammatory drugs such as indomethacin increase serum digoxin to levels high in the therapeutic range. This should be taken into consideration when co-administering other drugs known to increase the serum concentration of digoxin such as several antiarrhythmics.     

Postmortem digoxin-like immunoreactive substances (DLIS) in patients not treated with digoxin

Endogenous digoxin-like immunoreactive substances (DLIS) cross-react in immunoassays of digoxin. The postmortem rise in digoxin levels in patients treated with the drug may be due to its redistribution. It is unclear what is the contribution of DLIS to this increase and whether DLIS are present postmortem in patients not treated with digoxin. The objectives of this study were to determine whether DLIS are present after death in patients not treated with digoxin, whether a postmortem increase in DLIS is detectable and whether sampling site can affect DLIS concentrations. DLIS (measured as digoxin, TDx Abott) were determined in blood samples drawn antemortem from ICU patients; postmortem samples from femoral artery and cardiac chambers were taken at least 12 h after the death of these same patients. DLIS concentrations > or = 0.2 ng/ml were measured in 44 and 40% of patients antemortem and postmortem (femoral), respectively. No difference was found in DLIS levels between antemortem and postmortem femoral and cardiac samples. Age, ICU stay and postmortem sampling time did not affect the postmortem increase in DLIS. None of the levels was in the toxic range. DLIS may be present after death and their concentration does not increase postmortem. The interpretation of postmortem digoxin concentrations that fall in the therapeutic range should be done cautiously; such measurable levels do not necessarily indicate misuse or malicious intent even in patients who had not been treated with the drug.     

Therapeutic Drug Monitoring of Digoxin

Digoxin is a cardioactive drug with a narrow therapeutic range. Therapeutic drug monitoring is essential in clinical practice for efficacy as well as to avoid digoxin toxicity. Immunoassays are commonly used in clinical laboratories for determination of serum or plasma digoxin concentrations. Unfortunately, digoxin immunoassays are affected by both endogenous and exogenous compounds. Endogenous compounds are termed ‘digoxin-like immunoreactive substances’ (DLIS), which are found in elevated concentrations in volume-expanded patients. Exogenous compounds that interfere with digoxin assays are various drugs such as spironolactone, potassium canrenoate as well as Digibind® (Fab fragment of antidigoxin antibody), which is used in treating life-threatening digoxin overdose. Moreover, various Chinese medicines such as Chan Su, Lu-Shen Wan and oleander-containing herbal preparations also interfere with serum digoxin measurements by immunoassays. Monitoring unbound (free) digoxin concentration may under certain circumstances eliminate such interferences. Clinicians should be aware of limitations of therapeutic drug monitoring of digoxin using immunoassays.     

重症心力衰竭合并肾功能不全患者治疗的疗效分析

目的观察重症心力衰竭合并肾功能不全患者联合用药的远期疗效。方法对30例重症心力衰竭合并肾功能不全的患者，根据个体差异逐渐调整地高辛、依那普利、美托洛尔、氢氯噻嗪、螺内酯的用药剂量，长期随访观察2年。结果对重症心力衰竭合并肾功能不全患者长期联合用药治疗，随访显示，心功能明显改善（P〈0．001），未加重肾功能损害（P〉0．05），病死率下降。结论重症心力衰竭合并肾功能不全的患者，长期联合用药治疗，并根据血清肌酐清除率及地高辛浓度调整用药剂量，可有效改善心功能，不加重肾功能损害，并提高了生存质量。     

Loading dose of digoxin in renal failure.

1 Twenty-two dialysis dependent patients received an intravenous loading dose of digoxin of 10 microgram/kg and the mean +/- s.d. serum digoxin concentration 24 h later was 1.5 ng/ml +/- 0.4 (range 0.8--2.1 ng/ml). No evidence of toxicity was observed. 2 The average apparent volume of distribution of digoxin in dialysis dependent patients was found to be reduced by about one third compared with that reported for individuals with normal renal function, but there was great variation. 3 An appropriate intravenous loading dose of digoxin in most patients with advanced renal failure is 10 microgram/kg.     

Clinical study on digoxin tablets with high bioavailability (author's transl)

The relationship between different maintenance doses and the steady-state digoxin blood concentration was studied in 160 patients with heart failure. All patients received digoxin tablets of the same brand (Digacin). The bioavailability of this brand is 82% compared with an i.v. standard. During the treatment with daily doses of 0.2 mg and 0.3 mg average serum digoxin levels of 1.09 +/- 0.45 ng/ml and 1.33 +/- 0.53 ng/ml were measured in patients with normal renal function. The daily dose of 0.4 mg digoxin was in correlation to an average serum level of 1.75 +/- 0.81 ng/ml. 81% and 86% of all patients with normal renal function taking 0.2 or 0.3 mg digoxin every day were found to have levels in the range of 0.7 to 2.0 ng/ml. The influence of sex, age, height, body weight, maintenance dose, serum creatinine and serum potassium on the variance of the digoxin plasma levels was computed by multiple linear regression. The multiple correlation coefficient was r = 0.666, the coefficient of determination (100 r2) being 44.4%. Therefore 44.4% of the total variance could be explained by these variables. Individual variables accounted for the following percentages of the total variance: serum creatinine 29.1%; maintenance dose 14.5%; age 4.3%; and reciprocal of body weight 3.9%.     

Therapeutic drug monitoring of digoxin: impact of endogenous and exogenous digoxin-like immunoreactive substances

Digoxin is a cardioactive drug with a narrow therapeutic range. Therapeutic drug monitoring is essential in clinical practice for efficacy as well as to avoid digoxin toxicity. Immunoassays are commonly used in clinical laboratories for determination of serum or plasma digoxin concentrations. Unfortunately, digoxin immunoassays are affected by both endogenous and exogenous compounds. Endogenous compounds are termed 'digoxin-like immunoreactive substances' (DLIS), which are found in elevated concentrations in volume-expanded patients. Exogenous compounds that interfere with digoxin assays are various drugs such as spironolactone, potassium canrenoate as well as Digibind (Fab fragment of antidigoxin antibody), which is used in treating life-threatening digoxin overdose. Moreover, various Chinese medicines such as Chan Su, Lu-Shen Wan and oleander-containing herbal preparations also interfere with serum digoxin measurements by immunoassays. Monitoring unbound (free) digoxin concentration may under certain circumstances eliminate such interferences. Clinicians should be aware of limitations of therapeutic drug monitoring of digoxin using immunoassays.