The Pharmacokinetics of Recombinant Human Relaxin in Nonpregnant Women After Intravenous,Intravaginal, and Intracervical Administration

The pharmacokinetics of recombinant human relaxin (rhRlx) after intravenous (iv) bolus administration and the absorption of rhRlx after intracervical or intravaginal administration were determined in nonpregnant women. The study was conducted in two parts. In part I, 25 women received 0.01 mg/kg rhRlx iv. After a minimum 7-day washout period, these women were dosed intracervically (n = 10) or intravaginally (n = 15) with 0.75 or 1.5 mg rhRlx, respectively, in 3% methylcellulose gel. Part II was a double-blind, randomized, three-way crossover study in 26 women. At 1-month intervals, each woman received one of three intravaginal treatments consisting of 0 (placebo), 1, or 6 mg rhRlx in 3% methylcellulose gel. The serum concentrations of relaxin following iv administration were described as the sum of three exponentials. The mean (±SD) initial, intermediate, and terminal half-lives were 0.09 ± 0.04, 0.72 ± 0.11, and 4.6 ± 1.2 hr, respectively. Most of the area under the curve was associated with the intermediate half-life. The weight-normalized clearance was 170 ± 50 mL/hr/kg. The observed peak concentration was 98 ± 29 ng/mL, and the weight-normalized initial volume of distribution was 78 ± 40 mL/kg, which is approximately equivalent to the serum volume. If central compartment elimination was assumed, the volume of distribution at steady state (V _ss/W) was 280 ± 100 mL/kg, which is approximately equivalent to extracellular fluid volume. V _ss/W could be as large as 1300 ± 400 mL/kg without this assumption. After intravaginal administration of the placebo gel, endogenous relaxin concentrations were evident (i.e., 20 pg/mL) in 9 of the 26 women (maximum concentrations, 23–234 pg/mL). A similar proportion of women (approximately 35–40%) exhibited measurable serum concentrations of relaxin following intravaginal rhRlx treatment; this proportion increased to 90% following intracervical rhRlx treatment. For both routes of administration, the maximum serum concentrations of relaxin were usually within the range of values observed for endogenous relaxin, suggesting that the absorption of rhRlx was minimal.     

静脉输液拔针后按压血管时间的临床探讨

目的静脉输液拔针后,按压血管多长时间较为合适,目前尚无定论。旨在探讨按压血管的最佳时间,以便最大限度地减少皮下瘀血,减轻病人痛苦,保护静脉血管。方法对200例静脉输液病人拔针后不同按压血管时间的效果进行了观察,并根据统计处理结果进行分析、比较。结果拔针后4min左右较为合适,能够有效地防止瘀血,时间过长,多数病人难以坚持;过短则皮下瘀血率高。结论这种做法,克服了过去静脉输液拔针后,按压血管时间随意性较大的缺陷,应大力推广。     

异丙酚氯胺酮混合液静脉麻醉

选择 40例 ASA ～ 级病人行异丙酚氯胺酮 (1∶ 2 )复合静脉麻醉。结果麻醉诱导后血压、心率与麻醉前相比无明显变化 ,2 0 %病人出现一过性 SPO2 下降 (<94% )。麻醉诱导苏醒快 ,满意率高 ,恢复期无精神症状。表明异丙酚可控制氯胺酮的心血管兴奋作用和恢复期精神症状 ,氯胺酮可减轻异丙酚的心血管抑制作用。两者配伍是一种较好的短效静脉麻醉方式 ,但仍存在呼吸抑制作用 ,应引起注意。     

Pharmacokinetic and Pharmacological Profiles of Free and Liposomal Recombinant Human Erythropoietin After Intravenous and Subcutaneous Administrations in Rats

Purpose. Recombinant human erythropoietin (Epo) is used frequently through intravenous (i.v.) and subcutaneous (s.c.) administration for the clinical treatment of the last stage of renal anemia. We encapsulated Epo in liposomes to develop an alternative administration route. The purpose of our study was to evaluate the pharmacokinetics and the pharmacological effects of liposomal Epo in comparison with the Epo after i.v. and s.c. administration to rats. Methods. Epo was encapsulated in liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and soybean-derived sterol mixture (SS) prepared by the reversed-phase evaporation vesicle method. After filtration through a 0.1 m polycarbonate membrane, liposomes were gel filtered (Epo/liposomes). Results. Epo/liposomes showed higher pharmacological activity than Epo/liposomes before gel filtration after i.v. administration to rats. Non-encapsulated Epo lost its activity, whereas encapsulated Epo in liposomes retained it. The pharmacological effects of Epo/liposomes were greater than those of Epo after i.v. administration. Epo/liposomes afforded 3–9 times higher AUC, lower clearance and lower steady-state volume of distribution than Epo after both i.v. and s.c. administrations. Epo/liposomes had an improved pharmacokinetic profile compared with Epo. S.c. administration of Epo/liposomes at 7 h may penetrate primarily (40% of dose) through the blood as a liposome and partly (7% of dose) in lymph. Conclusions. Epo/liposomes may reduce the frequency of injections required for a certain reticulocyte effect in comparison to Epo. The lower clearance of Epo/liposomes may increase the plasma concentrations of Epo, which increases the efficacy.     

Is the IV obstructed or infiltrated? A simple clinical test

Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.     

Peripheral total parenteral nutrition employing a lipid emulsion (Intralipid): complications encountered in pediatric patients.

The clinical records of 180 pediatric patients who received Intralipid via peripheral veins at a single institution (1964-1977) were retrospectively analyzed, with particular reference to the complications of this form of therapy. Intralipid was used in a dose range of 2--4 g/kg/day in order to supply 40% of the daily calorie requirements. The patients were neonates, infants, children, and adolescents with a wide range of clinical diagnoses. Local complications associated with Intralipid therapy were minimal. Transient elevations in serum enzyme levels (SGOT, SGPT, and LDH) were observed in 4% of patients, but all of these returned to the normal range after cessation of therapy. Ten patients had histologic evidence of cholestasis, the significance of which is discussed. The lipid emulsion was employed in patients with preexisting hyperbilirubinemia with concomitant resolution of jaundice. Intralipid was administered to patients with known severe thrombocytopenia (secondary to sepsis or myelosuppression) with return of the platelet counts to normal levels during the course of infusion therapy. The use of Intralipid in patients with established sepsis did not delay its response to conventional surgical or antibiotic therapy. There were no instances of the "overloading" syndrome observed.     

Pharmacokinetics of methyldopa in healthy man

Summary The pharmacokinetics of 2-¹⁴C-L--methyldopa have been investigated in five healthy volunteers following intravenous and oral administration. In the intravenous study a bi-phasic plasma concentration curve was found both for chemically determined -methyldopa and for radioactivity. The plasma level of radioactivity differed significantly from chemically determined drug, a pattern which was also found in urine. This suggests the presence of unidentified metabolite(s). The difference between plasma disappearance and urine recovery of -methyldopa and radioactivity during the first 4 h after injection suggests distribution to an extravascular compartment. Plasma half-lives of total radioactivity and of unchanged drug were calculated. In three subjects, pharmacokinetic parameters for a two-compartment open body model were calculated from urine and plasma data. Urinary recovery of radioactivity was almost complete within 48 h after intravenous administration. After oral administration, however, only about 40 per cent of the radioactive dose was recovered in the urine, and it contained approximately equal amounts of unconjugated methyldopa, acid-labile conjugated methyldopa and unidentified metabolite(s). The acid-labile conjugate was found only after oral administration, which supports the theory of a mucosal conjugation process. The lack of acid-labile conjugated drug either in the plasma or urine after intravenous injection indicates that there is no enterohepatic circulation of this drug.     

High-dose immunoglobulin therapy for Guillain−Barré syndrome in Japanese children

BACKGROUND: Guillain-Barré syndrome (GBS) is an acute acquired demyelinating polyneuropathy, presumed to be immune-mediated. Intravenous immunoglobulin (IVIg) has been used to treat GBS and was found to be effective. However, a well-controlled study of pediatric GBS has not been conducted in Japan. Therefore, to evaluate the efficacy of IVIg in the treatment of GBS, an open-labeled study was performed in pediatric patients. METHODS: Participants in the study were required to be younger than 15 years old, and diagnosed as having moderate or severe GBS. IVIg (400 mg/kg per day) was administered to patients for five consecutive days. Predefined outcome measures were defined on a seven-point scale of motor function (Hughes' functional grade [FG]). RESULTS: Eleven patients were treated with IVIg. The median time taken to improve by one grade on the FG scale was 10.0 days after initial treatment. Two weeks after initial treatment, 72.7% of patients treated with IVIg improved by one or more grades, and 36.4% improved by two or more grades, measured on the FG scale. After 4 weeks an improvement by one or more grades was observed in 81.8% of patients, and two or more grades in 63.6% of patients. These improvement rates were markedly greater than would occur with the natural course of GBS1. Adverse events (subjective symptoms or abnormal laboratory findings) were observed in four patients, although all were temporary and mild. CONCLUSIONS: The authors conclude that IVIg is a safe and effective treatment for childhood GBS, which shortens the time to recovery.     

氧氟沙星加双黄连注射液静脉滴注致肝损害1例

氧氟沙星 (ｏｆｌｏｘａｃｉｎ)和双黄连 (Ｓｈｕａｎｇｈｕａｎｇｌｉ ａｎ)已成为临床常用的抗菌药 ,但其不良反应亦不可忽视。我们曾遇见 1例用该 2药治疗上呼吸道感染引起严重肝功能损害 ,报道如下。病人男性 ,2 1ａ。主要因咽痛、咯痰、发热 2ｄ入院。病人于入院前 2ｄ出现咽痛、咯黄痰、胸痛、发热 (Ｔ38.9℃ )。诊断为上呼吸道感染。在当地卫生所给予氧氟沙星注射液(四川科伦大药厂生产 ,规格 :1 0 0ｍＬ :0 .2ｇ批号 0 1 30 1 2 )0 .2ｇ(1 0 0ｍＬ) +双黄连注射液 (齐齐哈尔第二制药厂生产 ,规格 :每支 2 0ｍＬ批号 30 0 1 32 ) 2 0…     

静脉注射免疫球蛋白对急性川崎病患儿淋巴细胞凋亡的影响

通过观察静脉注射免疫球蛋白（ＩＶＩＧ）对川崎病（ＫＤ）患儿淋巴细胞凋亡（ＡＰＯ）的影响，进一步探讨ＩＶＩＧ对免疫性疾病的作用机理。对２６例川崎病患儿和２０名健康儿童外周血单个核细胞（ＰＢＭＣ）经抗－ＣＤ３单克隆抗体刺激培养不同时间（０，１２，２４，４８，７２小时）ＡＰＯ百分率和ＤＮＡ片断化分析，２６例患儿随机分为两组，阿司匹林＋ＩＶＩＧ治疗组（ｎ＝１６）和阿司匹林治疗组（ｎ＝１０），并对ＰＢＭＣ经植物血凝素（ＰＨＡ）刺激淋巴细胞增殖反应进行了观察。结果：ＫＤ患儿ＡＰＯ百分率和ＤＮＡ片断化较正常儿童明显降低（Ｐ＜０．００１）和延迟；ＩＶＩＧ治疗后，降低的ＡＰＯ百分率和延迟的ＤＮＡ片断化被逆转，同时与单用阿司匹林组比较，临床症状明显改善。淋巴细胞增殖反应下调（Ｐ＜０．００１）。外周血淋巴细胞ＡＰＯ下调可能参与了ＫＤ的发病。ＩＶＩＧ治疗ＫＤ的机理可能部分归于对被抑制的淋巴细胞ＡＰＯ的逆转。ＩＶＩＧ对其它淋巴细胞凋亡不足的自身免疫性疾病治疗可能存在同样机理。