The Binding of Cyclosporin A to Human Plasma: An in Vitro Microdialysis Study

Purpose. The human plasma binding of cyclosporin A was studied in vitro using the technique of microdialysis. The effect of temperature on the overall binding interaction between cyclosporin A and human plasma was also investigated. Methods. Flow-through loop-type microdialysis probes were constructed from fused silica tubing and regenerated cellulose tubing with a MWCO of 13000 daltons. Probes were perfused with phosphate buffer (0.5 µl/min) and the concentration of ³H-cyclosporin A in the well-mixed medium (plasma or buffer) was 1200 ng/ml. Relative recoveries of cyclosporin A from plasma or buffer were determined for each probe by separate experiments to measure the solute gain or loss with reference to the perfusate. Results. Recoveries determined by loss were significantly greater than those determined by gain and in each case temperature dependent, with higher recoveries at higher temperatures. The plasma free fraction of cyclosporin A calculated from the recovery data and the perfusate to plasma concentration ratios was dependent on temperature in a log-linear fashion. Mean ± s.d. plasma free fractions expressed in percent were 33.5 ± 4.6, 17.9 ± 3.6, 6.2 ± 0.8, 3.0 ± 0.6, and 1.5 ± 0.2 at temperatures of 4, 10, 20, 30, and 37°C, respectively. Assuming that the enthalpy of binding is constant over the temperature range studied and pseudo-first order conditions exist, the binding reaction at these temperatures was spontaneous, endothermic (H = 74.0 kJ/mole), and entropically driven (S = 0.274 kJ/mole/deg). Conclusions. These results show that the free fraction of cyclosporin A in human plasma is dependent on temperature with the fraction unbound decreasing with temperature in the range of 4 to 37°C. The thermodynamic parameters for the binding of cyclosporin A to plasma components indicate that the reaction is a spontaneous endothermic reaction that is mainly entropy driven, similar to the partitioning of lipophilic molecules from an aqueous to a hydrophobic phase. Moreover, these results show that microdialysis is a feasible method to determine the binding interactions between plasma and cyclosporin A, which indicates the method may be suitable for other difficult binding studies where the solutes have nonspecific binding to separation devices.     

Prognostic significance of the evolution of left ventricular ejection fraction in patients with acute myocardial infarction not treated with thrombolytic therapy

Several controlled trials on the thrombolytic treatment of acutemyocardial infarction (AMI) have failed to demonstrate thatthrombolysis has a simultaneous positive effect on left ventricularfunction and survival. One explanation may be that spontaneouschanges in left ventricular function occurred during the progressionof AMI in control patients. The aim of this study was to evaluatethe spontaneous evolution of left ventricular ejection fraction(LVEF) and its prognostic influence on early (1 month) and late(1 year) mortality in patients with AMI. We studied 216 patientsadmitted to our CCU within 24 h of the onset of symptoms. LVEFwas determined by radionuclide ventriculography on admission(RNV1) and at the end of the necrotic phase (RNV2). Fourteenpatients died before RNV2. On the basis of LVEF values at RNV1,the remaining 202 patients were divided into two groups: thosewith a normal LVEF (55%), and those with an abnormal LVEF (<55%). Among patients with a normal LVEF at RNV1 (64 patients) a significantincrease (>12%) in LVEF at RNV2 was observed in 12.5%, asignificant decrease (>12%) in 12.5% and no change at allin 75%. All of these patients survived, regardless of the evolutionof LVEF. In patients with an abnormal LVEF at RNV1 (138) a significantincrease (>5%) in LVEF at RNV2 was observed in 72.5%, a significantdecrease (>5%) in 6.5% and no change at all in 21%. In patientswith a LVEF increase, both early and late mortality were significantlylower than in patients with a LVEF decrease: (early mortality4% vs 55.5%, P<0.001; late mortality 6% vs 66.6%, P<0.001)respectively. In patients without any LVEF change, mortalitywas significantly lower than in patients with a LVEF decrease:(early mortality 10% vs 55.5%, P = 0.01; late mortality 14%vs 66.6%, P=0.004) respectively. In conclusion, our data demonstrate that a significant increasein LVEF occurs in most patients with an early depression ofleft ventricular function. This behaviour is associated witha low early and late mortality in comparison with the patientswith a LVEF decrease and is independent of thrombolytic treatment.When the early measurement of LVEF is normal the prognosis isnot influenced by LVEF evolution. These findings must be keptin mind when LVEF is used as a prognostic index and as an end-pointfor the evaluation of the effects of thrombolytic therapy.     

Radioisotope assessment of heart damage in hypertransfused thalassaemic patients

Twenty-five thalassaemic patients treated with repeated blood transfusion (BT) and intensive iron removal therapy were studied by echocardiography and rest/stress equilibrium gated radionuclide angiocardiography (EGNA). Stress left ventricular ejection fraction (LVEF) showed an important negative correlation with number of BTs (r = –0.75). Abnormal values of stress LVEF were measured after 200 BTs: these data demonstrate the effectiveness of stress LVEF in the follow-up of patients who have undergone repeated BTs and the clinical importance of intensive chelation therapy. Peak filling rate did not show diagnostic value in the early detection of iron cardiotoxicity. However, its inverse correlation with BT (r = –60) indicates that iron overload depresses the diastolic parameters.     

Prognostic potential of flow cytometric S-phase and ploidy prospectively determined in primary breast carcinomas

In a prospective study of a consecutive breast cancer series accumulated in the period 1978–82, the S-phase fraction (SPF) and ploidy status were determined by flow cytometry performed on cell nuclei derived from samples of 580 primary tumors. Sixty percent of the tumors were non-diploid. After correction for debris the median SPF values were 7.3% overall, 12% for non-diploid tumors, and 2.9% for diploid tumors (2.6% when nodal subsets N2 and N3 and cases with metastases at presentation were excluded). The SPF values correlated both to tumor size (p=0.008) and to the number of positive axillary lymph nodes (p=0.03).At clinical follow-up in 1986, 467 unilateral breast cancer patients who had undergone radical treatment for cure could be evaluated with respect to the prognostic value of both the SPF value and ploidy status. The median duration of follow-up was then 59 months (range 2–90), and the median time-to-recurrence 24 months (range 2–69, n=137).At follow-up in 1991, 201/467 of the patients had died, the median duration of follow-up being 50 months (range 2–126) for the deceased, and 119 (range 6–148) for the survivors. In multivariate analysis (Cox's proportional hazards models), the strongest independent predictors of distant recurrence-free survival (DRFS) were the number of positive axillary lymph nodes (p<0.0001), the debris-corrected SPF value alone (p=0.003,versus p=0.05 for uncorrected value), and ploidy status combined with the corrected SPF value (p=0.0002). When age was taken into account, both the corrected SPF value and the ploidy-SPF combination were predictors of crude survival (p=0.006 and p=0.002, respectively).In univariate life-table analysis, the 5-year DRFS rate was 93% in node-negative (N0) cases with an SPF<7.3%, as compared to 80% in those with an SPF7.3% (p=0.005). Among node-positive cases, the prognostic value of the SPF was confined to those with 1–3 positive nodes, the 5-year DRFS rate being 68% in cases with an SPF<7.3%, as compared to 40% in cases with an SPF7.3% (p=0.01).Ploidy status and SPF were combined to form four groups: diploid & SPF<2.6% (DL), diploid & SPF2.6% (DH), non-diploid & SPF<12% (NDL), and non-diploid & SPF12% (NDH). Among node-negative patients, the DRFS rate fell from 95% in the DL group to 87% in the NDL group, with the DH group at an intermediate level, as compared with 74% (p=0.03) for the NDH group which accounted for the bulk of the early distant recurrences. Among patients with 1–3 positive lymph nodes, the 5-year DRFS rate was 68% in both the groups with low SPF values (DL and NDL), as compared with 45% in the DH group (p=0.03), and 37% in the NDH group (p=0.006).In this study, the flow cytometry SPF value, alone or in combination with ploidy status, yielded the most profound additional prognostic information, enabling both node-negative patients with a high probability of cure and patients at risk of early relapse to be identified. Among node-positive patients, the prognostic value of the SPF value was confined to those with 1–3 positive axillary lymph nodes (the predominant node-positive subgroup), enabling a high and a low DRFS rate subgroup to be distinguished – a useful distinction where selection for adjuvant drug treatment is concerned. As the predictive strength of the SPF value was enhanced when correction was made for debris, we would recommend that the effect of such factors as debris be minimized as far as possible when flow cytometry-derived SPF values are to be used for prognostic purposes.     

Superficial liposuction: A new application of the technique for aged and flaccid skin

From 1982 to 1991, 2500 patients underwent liposuction to thin the superficial areolar layer of fat. The patients were of all ages and had different types of skin. From the results the author concludes that the new superficial liposculpting, based on the controlled scar retraction of the thin cutaneous adipose flap remaining after the treatment, allows for very good results even in very flaccid and aged skin. A digital molding of the residual fat also improves the contouring. So-called cellulite is finally meliorated.Presented at the First and Second International RAPS Congress, Sao Paulo, Brasil, March 1989 and 1991 and at the Nineth LSNA Meeting, Seattle, Washington, September 1991     

Syringe liposculpture: A two-year experience

Syringe liposcupture is a method that combines two relatively new techniques of plastic surgery: syringe liposuction and fat grafting. We can reshape the face and the body by removing localized fat deposits and reinjecting this fat where needed. When we do not reinject, we call the technique reduction liposculpture. In 1989 we introduced a new technique—superficial syringe liposculpture—to treat patients with flaccid skin, superficial irregularities or depressions, cellulite, and liposuction sequelae. The technique combines syringe liposculpture, superficial liposuction, and our method of treating skin irregularities by breaking the fibrous adherences and injecting fat superficially.     

板蓝根抑菌抗炎活性部位的评价

目的：评价和比较板蓝根5个化学部位抑菌、抗炎活性的强弱。方法：采用管碟法测定板蓝根不同化学部位对于金黄色葡萄球菌、铜绿假单胞菌的敏感性，观察对二甲苯所致小鼠耳廓肿胀的抑制作用。结果：板蓝根Ⅴ部位体外抑菌活性最强，Ⅴ部位具有显著的抗炎活性。结论：板蓝根中高极性成分具有很强的药理活性，是其发挥清热解毒功效的物质基础。     

Influence of body composition on quantitative ultrasound parameters of the os calcis in a population-based sample of pre- and postmenopausal women

Body mass is known to be related to measures of bone mineral density (BMD) as well as to parameters of quantitative ultrasound (US). To examine the effect of the body compartment's fat mass and lean body mass on quantitative ultrasonic bone parameters, data from a sample of 3241 German women were analyzed. Anthropometric measures, including skinfold thickness, were obtained from standardized measurements, and fat and lean body mass were derived from classical regression formulas based on skinfold measurements. Ultrasonic bone measurements were performed on the right os calcis, and speed of sound (SOS) and broadband ultrasound attenuation (BUA) were determined. Women were grouped into pre- and postmenopausal status; postmenopausal women were further stratified into ever and never hormone-replacement user. Correlation analysis indicated lean body mass to be stronger correlated with BUA than fat mass in both pre- (r = 0.23; P= 0.0001) and postmenopausal women with (r = 0.19; P= 0.0001) and without hormone replacement therapy (HRT) (r = 0.26; p = 0.0001). SOS demonstrated very small or no associations with body mass or its components. Multiple linear regression models were used to describe the relationship among body weight, fat mass, and lean body mass on BUA after adjustment for confounding variables. Both in pre- and postmenopausal women lean body mass was more strongly related to BUA than fat mass. However, body mass measures explained only small amounts of the overall variance in BUA (R²= 1–3% in premenopausal women; R²= 1% postmenopausal with HRT; R²= 4–5% in postmenopausal women without HRT). In conclusion, the strong influence of body mass and its components previously reported for BMD was not observed for quantitative ultrasonic bone parameters. Received: 5 January 1999 / Accepted: 1 July 1999     

大青叶抗内毒素活性部位筛选

目的 评价和比较大青叶5个化学部位的抗内毒素作用。方法 采用动态浊度法测定细菌内毒素浓度，观察大青叶不同化学部位对放线菌素D敏化小鼠内毒素致死攻击的保护作用。并以内毒素制备家兔发热模型，测定其肛温变化。结果 大青叶Ⅳ部位能直接中和降解内毒素，显著降低内毒素的致热性和致死性。结论 大青叶Ⅳ部位具有显著的体内外抗内毒素活性。     

中药鬼箭羽提取物对脂肪细胞葡萄糖摄取作用的影响

目的：在对中药鬼箭羽药效学研究的基础上，初步探讨其各提取组份SML-1，SML-2，SML-3，SML-4对于脂肪细胞的降糖作用机制。方法：采用分离的大鼠脂肪细胞，用高浓度葡萄糖和胰岛素诱导脂肪细胞胰岛素抵抗模型，观察鬼箭羽各提取组份对于胰岛素抵抗模型脂肪细胞的葡萄糖摄取的影响以及对于正常脂肪细胞，低浓度胰岛素刺激脂肪细胞的影响。结果：鬼箭羽各提取组份SML-1，SML-2，SML-4(10μg/ml)对脂肪细胞葡萄糖的基础摄取率有所提高。SML-2，SML-3(100μg／ml)；SML-1，SML-2，SML-3，SML-4(10μg/m1)；SML-1，SML-3，SML-4(1μg／ml)；SML-1，SML-2，SML-3(0．1μg／ml)对于低浓度胰岛素(1．2nmol／L)刺激的外周葡萄糖摄取均有协同增强作用。SML-1，SML-2，SML-3，SML-4(100μg／ml)；SML-1，SML-2，SML-3，SMI-4(10μg／ml)；SML-1，SML-2(1μg／ml)；SML-1，SML-2(0．1μg／ml)可以提高胰岛素抵抗脂肪细胞的葡萄糖摄取水平。结论：鬼箭羽各提取组份可以促进正常脂肪细胞低浓度胰岛素刺激脂肪细胞的葡萄糖摄取，促进胰岛素抵抗脂肪细胞的葡萄糖摄取可能是其降糖作用机制之一。