In vivo pharmacokinetic and pharmacodynamic evaluation of the malononitrilamide FK778 in non-human primates

The malononitrilamide FK778 is a leflunomide analogue with a shorter half-life than leflunomide. Groups of cynomolgus monkeys were treated orally with various doses of FK778 once daily for 7 days: group A, 10 mg/kg ( n=4); group B, 5 mg/kg ( n=3); and group C, one single loading dose of 20 mg/kg followed by 5 mg/kg once daily ( n=2). Trough plasma concentration of FK778 was measured by HPLC. Lymphocyte proliferation and expression of T-cell activation surface antigens were assessed by flow cytometry. In group A, trough plasma concentration of FK778 reached steady state at 48 h. After 7 days, lymphocyte proliferation was 23+/-7.4% (mean +/- SEM) and expression of CD71, CD25, CD11a and CD95 on T cells was less than 50% of pre-treatment baseline values. In group B, trough plasma levels of FK778 did not reach steady state, but dropped to near-zero levels after 3 days and on day 7 and lymphocyte proliferation and T-cell surface antigen expression were not different from pre-treatment baseline values. In group C, FK778 trough levels did not reach steady state, but drug exposure was evident over the entire period of treatment, and on day 7, lymphocyte proliferation was 11.4+/-8.6% of pre-treatment baseline values. We conclude that FK778 inhibits lymphocyte proliferation and expression of T-cell activation antigens in vivo in non-human primates after 1 week of treatment. These effects are related to the total drug exposure over the time of treatment. At doses lower than 10 mg/kg daily, FK778 is cleared from the circulation between the dosing intervals, thus failing to exert its inhibitory effects on immune functions.     

Anti-Gal alpha 1-3Gal IgM and IgG antibody levels in sera of humans and old world non-human primates

Organs transplanted from pig to primate are rejected within minutes or hours by an antibody-dependent, complement-mediated mechanism [hyperacute rejection (HAR)]. Even after depletion of anti-Galα1-3Gal (Gal) antibody (Ab), for example by extracorporeal immunoadsorption, return of natural Ab is believed to be a major factor in the initiation of acute humoral xenograft rejection. Various non-human primates are used as recipients of pig organs in experimental discordant xenotransplantation (XTx) models. However, anti-Gal IgM and IgG levels in non-human primates may differ from those in humans. Serum levels of anti-Gal IgM and IgG were measured by enzyme-linked immunosorbent assay (ELISA) in humans (n=14), chimpanzees (n=8), baboons (n=214), cynomolgus monkeys (n=29), rhesus monkeys (n=23) and Japanese monkeys (n=6). The mean level of anti-Gal IgM was significantly higher in chimpanzees than in other groups, while in rhesus monkeys it was significantly lower than in other groups, except baboons and Japanese monkeys. The mean human anti-Gal IgG level was higher than in other groups and this difference reached statistical significance except with regard to chimpanzees. The mean anti-Gal IgG level in baboons was significantly lower than that in humans, chimpanzees and cynomolgus monkeys. The measured differences in anti-Gal IgM and IgG levels may affect the kinetics of Ab removal and rate of return in different species, and thus may have relevance for translating work in non-human primate models to the clinical setting.     

A computer program for the storage and retrieval of urodynamic data

The computer is idcally suited for storing and retrieving a large volume of medical data. Described herein is a computer program written for the managemenr of data from patients who have had urodynamic evaluation. The program is highly user-oriented and requires only minimal training of personnel. The required hardware is reliable and relatively inexpensive. Further. the program is flexible and easily modified for use in other subspecialty areas of urology.     

Innovation in urodynamic testing: Report of the first fully computerized work station

We have conducted the first clinical trials on a new fully computerized urodynamic instrument on a referral population of 1,690 patients. The instrument performed the full range of urodynamic tests equivalent to that of a six-channel strip chart recorder. The computer was found capable of recording urodynamic tracings, storing the data on computer files, and generating graphic summaries of test results. The computerized work station was found to be easy to operate, safe for patient use. accurate in reporting results, and durable in active clinical use. Computer technology is proven well adapted to urodynamic testing with both clinical and research applications.     

Transurethral incision of congenital obstructive lesions in the posterior urethra in boys and its effect on urinary incontinence and urodynamic study

Study Type – Therapy (case series)
Level of Evidence 4 What’s known on the subject? and What does the study add? We have clarified that there exist two types of voiding urodynamics (pressure‐flow‐study) for congenital urethral obstruction in boys; one is synergic pattern (SP) and the other is dyssynergic pattern (DP). In terms of daytime incontinence and nocturnal enuresis, the transurethral endoscopic incision of these obstructive lesions is only effective in the SP type, while never effective in the DP type. The synergic pattern (SP) seems to represent simple anatomical obstruction, while the dyssynergic pattern (DP) may represent anatomical obstruction complicated with functional obstruction. The efficacy of endoscopic incision to mild forms of congenital urethral obstruction has been controversial, especially in terms of nocturnal enuresis. One of the reasons for the controversy is due to the lack of pre‐and post‐operative urodynamic assessment with its linkage to symptomatic change. We have, for the first time in the world, systematically conducted voiding urodynamic study for those elusive lesions seen in enuretic boys. Conclusively, for simple mechanical obstruction (SP), we confirmed that some voiding urodynamic parameters improve after the endoscopic incision, parallel to symptomatic improvement, while in the rest (DP) endoscopic incision is never effective. The cause of this ineffectiveness seemed to be due to persistent functional obstruction having superimposed on mechanical obstruction. The result of the study urges us to be more keen to diagnose and treat the mild congenial urethral obstruction as well as the concomitant functional obstruction in boys with nocturnal enuresis.

OBJECTIVE

? To evaluate the clinical significance of congenital obstructive lesions of the posterior urethra in boys with refractory primary nocturnal enuresis.

PATIENTS AND METHODS

? VCUG was performed in 43 consecutive boys who visited our department from April 2004 to April 2009 who were unresponsive to conservative treatment. 20 patients of the 43 patients, underwent TUI. VCUG and UDS were performed before and 3–4 months after TUI. ? In UDS, the maximum flow rate (Q_max), maximum bladder capacity, and post‐voiding residual urine volume were determined using uroflowmetry (UFM), and the detrusor pressure (P_det) at Q_max was determined in a pressure flow study (PFS). ? Clinical outcome was evaluated 3–4 months and 6 months after TUI.

RESULTS

? In VCUG performed 3–4 months after TUI, improvement was observed in urethral morphology in all patients. In preoperative PFS, two patterns were observed: 13 patients (65%) had a synergic pattern (SP) in which the P_det increased with increasing urinary flow rate simultaneously with the initiation of voiding and seven (35%) had a dyssynergic pattern (DP) in which the P_det was not coincident with the initiation of voiding, but was higher immediately before voiding than at Q_max. TUI was effective only in the SP group: symptomatic improvement was observed in 87.5% of patients with daytime incontinence and 77% of patients with nocturnal enuresis 6 months after TUI. ? In the DP group, no effect was observed (0%). With regard to changes in UDS parameters, a significant decrease (P= 0.0004) was observed in the P_det at Q_max and a significant increase (P= 0.036) was observed in the maximum bladder capacity in the SP group, whereas no significant differences were noted in any parameters in the DP group.

CONCLUSION

? Two voiding urodynamic patterns with different clinical outcomes of TUI were detected among patients with congenital posterior urethral obstruction, the underlying disease of refractory primary nocturnal enuresis in boys.     

Pharmacodynamics of anticholinergic agents measured by ambulatory urodynamic monitoring: A study of methodology

The aim of the study was to establish a methodology whereby ambulatory urodynamic monitoring (AUM) may be used in the assessment of the effects of darifenacin on urodynamic measures of detrusor function and symptoms associated with detrusor instability. Six patients (one man and five women) with detrusor instability (DI) on conventional urodynamic monitoring were recruited into this placebo-controlled crossover study. The study was divided into two periods of 7 days of treatment with either darifenacin 5 mg t.d.s. or placebo with the patient crossing over to the alternative treatment after a washout period of 7 days. On the 7th day of each treatment, AUM was carried out. Parameters used to quantify detrusor activity on AUM were the number, amplitude, and duration of detrusor contractions and the total area under the detrusor pressure/time curve. “Events” recorded were urge, leakage episodes, voids, and pain. Six comparable hours of AUM for each treatment period could be analyzed in four patients and 4 hr in one. In three of the five patients, reduction in activity on AUM while on darifenacin was apparent. Symptom data closely matched the changes in detrusor activity measured on AUM. This is the first study reporting the use of AUM in the development of a drug with an effect on detrusor activity. AUM has clear advantages over conventional cystometry, which can only measure surrogate urodynamic parameters at a single time point. The optimal duration of monitoring in this context appears to be 6 hr with prolongation of monitoring time beyond this being unlikely to yield additional useful information. Correlation between symptoms and findings on AUM is good with changes in parameters recorded on AUM relating closely to the improvement in symptoms. Neurourol. Urodynam. 18:223–234, 1999. © 1999 Wiley-Liss, Inc.     

Platelet aggregation in humans and nonhuman primates: relevance to xenotransplantation

Iwase H, Ekser B, Zhou H, Dons EM, Cooper DKC, Ezzelarab MB. Platelet aggregation in humans and nonhuman primates: relevance to xenotransplantation. Xenotransplantation 2012; 19: 233–243.. © 2012 John Wiley & Sons A/S. Abstract: Introduction: Platelet activation/aggregation plays a key role in the dysregulation of coagulation and the development of thrombotic microangiopathy in nonhuman primate recipients of pig xenografts. As a preliminary to the study of anti‐platelet therapy in vitro and in vivo, the present study aimed to compare platelet aggregation in whole blood from humans, baboons, and cynomolgus monkeys. Methods: Using “Chrono‐log” technology (two‐sample four‐channel Chrono‐log Whole Blood Aggregometer), we studied aggregation of platelets in healthy humans (n = 8), baboons (n = 5), and monkeys (n = 8). Whole blood (WB) samples were collected, and platelet aggregation was assessed using three different volumes of blood (1, 0.5, and 0.25 ml). Platelet activation was induced using collagen (at 3 and 5 μg/ml), ristocetin (at 0.5 and 1.0 mg/ml), adenosine diphosphate (ADP; at 10, 20, and 40 μm ), or thrombin (at 1 and 5 IU/ml). Inhibition of agonist‐induced platelet aggregation by heparin and low molecular weight heparin (LMWH) (at 1, 10, and 100 IU/ml) was evaluated. Results: Mean platelet counts were 222.1, 263.2, and 276.1 (×10³/μl) in humans, baboons, and monkeys, respectively. In all three species, platelet aggregation was induced by collagen, ristocetin, ADP, or thrombin in a dose‐dependent manner. A blood volume of 0.5 ml provided the most consistent results with all agonists in all three species. Dilution studies indicated that there was a significant positive correlation between platelet count and percent aggregation of platelets (P < 0.05). Collagen (3 and 5 μg/ml), ADP (10, 20, and 40 μm ), and thrombin (1 and 5 IU/ml) induced significantly greater platelet aggregation in humans than in baboons. ADP (20 and 40 μm ) and thrombin (1 and 5 IU/ml) induced significantly greater platelet aggregation in monkeys than in baboons. There was no species difference with ristocetin (0.5 or 1.0 mg/ml). In all species, thrombin (1 or 5 IU) induced greater platelet aggregation than any of the other reagents. Heparin at 1 IU/ml and LMWH at 10 IU/ml in all species almost completely abrogated thrombin‐induced platelet aggregation. Heparin at 100 IU/ml effectively inhibited platelet aggregation induced by collagen, but only partially inhibited aggregation induced by ADP or ristocetin. LMWH only partially inhibited aggregation induced by collagen, ristocetin, and ADP. Conclusions: The “Chrono‐log” technology proved to be a reliable method of evaluating platelet activation and aggregation in vitro in primates. Species differences may play a role in platelet aggregation, with the monkey being more comparable to the human than the baboon, although overall trends were similar. In all species, thrombin induced greater platelet aggregation than other agonists. Even a concentration of heparin of 1 IU/ml, which is probably the maximal concentration that is clinically‐applicable, prevented platelet aggregation induced by thrombin, but was less effective in preventing aggregation induced by collagen, ADP, or, particularly, ristocetin.     

A new video urodynamics: Combined ultrasonotomographic and urodynamic monitoring

A new video urodynamics to evaluate lower urinary tract function is presented. Video urodynamics was described originally as a combined radiographic and urodynamic monitoring. We describe certain modifications of original method, using the ultrasonotomographic method instead of the radiographic method. The urodynamic data and the simultaneous ultrasonotomography can be displayed through the display controller on the color display monitor. Our technique will be an extremely reliable method for the evaluation of lower urinary tract function.     

糖尿病大鼠膀胱和脊髓背根神经节中P75的表达与尿流动力学改变

目的探讨糖尿病大鼠膀胱与脊髓背根神经节（DRG）中神经生长因子受体P75的表达及尿流动力学改变。方法建立糖尿病大鼠模型20只，以15只正常大鼠为对照，应用免疫组化方法，分别检测大鼠膀胱组织及DRG中P75的变化情况，结合尿流动力学改变，探讨糖尿病膀胱病变（DC）可能的发病机制。结果与对照组比较，糖尿病组膀胱湿重增加[（171．150±6．081）vs（135．530±5．330）mg]，最大膀胱容量增加[（2．97±0．54）mLvs（1．73±0.23）mL]，储尿期膀胱压降低[（0．39±0．05）vs（0．77±0．06）kPa]，最大膀胱压力降低[（2．98±0．12）vs（5．99±0．25）kPa]（P均〈0．05）。无论是在膀胱组织还是在DRG中，糖尿病组P75的表达均低于对照组，有统计学意义（P〈0．05）。结论神经生长因子的受体P75在膀胱与脊髓背根神经节中的异常表达可能与DC的发病机制有关。     

A comparative study of a single-incision sling and a transobturator sling: clinical efficacy and urodynamic changes

Introduction

In this retrospective study, a comparison is made of the clinical efficacy of two stress urinary incontinence treatment apparatuses, a single-incision sling and a transobturator sling.

Methods

Eighty-five (single-incision n?=?43, transobturator n?=?42) consecutive patients were included in this study. Clinical outcomes were assessed by the cough stress test (CST), the pad test, the Impact Questionnaire-Short Form (IIQ-7), the Urogenital Distress Inventory six-item questionnaire (UDI-6), the Sexual Questionnaire-SF (PIS-Q), the pain score, and the postoperative changes in urodynamic parameters. A comparison of the 1-year follow-up data is presented.

Results

Three months post-surgery, 81.8% of the single-incision sling group and 74.4% of the transobturator sling group had a negative cough test and a dry pad test. One year after surgery, significantly decreasing UDI-6, IIQ-7, and increasing PIS-Q scores were observed in both groups, while the complication rates remained similar. Postoperatively, the single-incision sling group seems to show a greater improvement in UDI-6 score, require less operation time, and experience less blood loss, less postoperative pain, and a smaller decrease in maximal urethral closure pressure (MUCP).

Conclusions

These results suggest that the single-incision sling and the transobturator sling are equally as effective and safe for the treatment of stress incontinence, as evaluated during the 1-year follow-up. The insertion of a single-incision sling seems to be less painful than that of a conventional sling. One year after surgery, the MUCP and mean flow rate of the transobturator sling group had significantly decreased compared with that of the single-incision sling group.     

Irritable bladder syndrome in an animal model: A continuous monitoring study

Irritable bladder syndrome (IBS) was induced in four female African green monkeys (Cercopithecus aethiops) by the use of intravesical instillation of acetone. The animals were housed in a modified metabolic cage for continuous micturition monitoring, and two uroflowmeters connected to a remote PC monitored the frequency, voided volumes, and peak flows. Before and after, urea absorption studies and urodynamics were obtained for each animal. Urea absorption increased significantly after acetone instillation and returned to baseline after 4 weeks (26 to 66 to 32%). Intravesical acetone instillation produced marked effects on bladder physiology in the first week. Bladder compliance dropped from a baseline of 10.47 to 0.58 ml/cm H₂O. The voiding pattern changed from a normal pattern with a mean voided volume of 17.58 ml into marked increase in frequency and dribbling pattern with few voids (mean = 5.03 ml). Systematic behavioral observations were carried out for 4 hours per day utilizing an observation program on a laptop computer. Activity patterns, attention, sterotypic behaviors, and self-directed activities were recorded for each monkey. The animals demonstrated decreased frequency of activity and increased frequency in self-directed activities (groom, scratch), behaviors consistent with an animal experiencing pain or discomfort. The findings suggested that IBS induction in monkeys is feasible and produces a clinical picture similar to interstitial cystitis in humans. It offers a suitable animal model to enhance the understanding of voiding dysfunction with its neural pathways and to test the different therapeutic modalities to control IBS. © 1995 Wiley-Liss, Inc.     

Urodynamic parameters in patients with slight and severe genuine stress incontinence: Is the stress profile useful?

This study evaluates the usefulness of the urethral pressure profile (UPP) parameters in assessing the severity of genuine stress incontinence (GSI). Functional length (FL), maximum urethral closure pressure (MUCP), pressure transmission ratio (PTR), residual area at stress (RAS), number of patients with incontinent spikes (IS), and distribution of IS on UPP were determined in supine and standing position for 54 patients (group I) with a 1 -hour pad test < 2 g and compared with the values of 63 patients (group 2) with a 1 -hour pad test > 2 g. The results were similar: FL (supine: 24 mm ± 6/26 mm ± 7 [P:0.2]; standing: 26 mm ± 8/24 mm ± 11 [P:0.5]); MUCP (supine: 51 cm H₂O ± 23/47 cm H₂O ± 20 [P:0.3]; standing: 45 cm H₂O ± 21/38 cm H₂O ± 18 [P:0.1]); and PTR (supine: 83% ± 27/84% ± 31 [P:0.9]; standing: 81% ± 25 and 88% ± 27 [P:0.3]). But the RAS was lower (supine: 502 mm² ± 497/246 mm² ± 268 [P < 0.009]; standing: 500 mm² ± 534/271 mm² ± 306 [P < 0.05]) in group 2. If the percentage of patients with IS was higher (supine: 57/93% [P < 0.001 ]; standing: 54/84% [P] < 0.011) in group 2, the distribution of IS over the entire FL demonstrated no differences between group 1 and 2. In conclusion, except for the RAS, standard UPP parameters cannot be considered determinant in assessing the severity of GSI. © 1994 Wiley-Liss, Inc.