Electromotive versus passive diffusion of mitomycin C into human bladder wall: concentration-depth profiles studies.

The objectives of these investigations were: (a) to make a preliminary study to assess concentration-depth profiles of mitomycin C (MMC) in the bladder wall at specified time intervals after passive diffusion (PD); and (b) to conduct a major study to compare concentration-depth profiles after PD and electromotive drug administration (EMDA) of MMC. Full thickness sections of viable human bladder wall were placed in two-chamber cells with urothelium exposed to donor compartments containing 40 mg of MMC in 100 ml of 0.96% NaCl solutions and with serosa-facing receptor compartments containing 0.9% NaCl solutions. In the preliminary study during each of nine experimental sessions, five sections of bladder wall were individually exposed to MMC for either 5, 15, 30, 45, or 60 min. In the major study, an anode and a cathode were sited in the donor and receptor compartments, and 14 paired experiments--current (20 mA)/no current--were conducted over a 30-min period. Bladder wall sections were cut serially into 40-microm slices parallel to the urothelium and analyzed by high-performance liquid chromatography for MMC concentration (microg/g wet tissue weight). Tissue viability and morphology and MMC stability were assessed by trypan-blue exclusion test, histological examination, and mass spectrometry analysis. In the preliminary study (PD only), mean MMC concentrations (microg) at 5, 15, 30, 45, and 60 min were: (a) for urothelium, 15.3, 60.0, 58.2, 60.1, and 57.8, respectively; (b) for lamina propria, 2.2, 18.9, 19.3, 16.1, and 17.3, respectively; and (c) for muscularis, 0.4, 2.0, 1.8, 1.3, and 2.4, respectively. In the comparative study, MMC concentrations and coefficients of variation (CV) were as follows: (a) for urothelium after PD, 46.6 with CV = 69%, and after EMDA, 170.0 with CV = 43% (P < 0.0001); (b) for lamina propria after PD, 16.1, with CV = 60%, and after EMDA, 65.6 with CV = 29% (P < 0.0001); and (c) for muscularis after PD, 1.9 with CV = 82%, and after EMDA, 15.9 with CV = 82% (P < 0.0005). All of the bladder sections remained viable, and the chemical structure of MMC was unchanged. It was concluded that EMDA significantly enhances MMC transport into all of the layers of the bladder wall, and sections of viable human bladder are a reliable tool for assessing different modes of drug delivery.

Effect of osmotic pressure on uptake of chemotherapeutic agents by carcinoma cells.

Intraperitoneal chemotherapy has been used to treat cancers which are confined to the abdominal cavity. Several variables which affect drug delivery into tumor cells have been identified, but the effect of osmotic pressure has not been studied. Tumor cell lines were used to evaluate the effect of fluid tonicity on drug uptake. HeLa cells and a murine teratoma cell line were suspended in solutions of tonicities 154, 308, and 616 mosM, each containing the same quantity of 5-fluorouracil, and uptake of the drug was measured at different intervals over 30 min. At all time points the amount of 5-fluorouracil taken up by cells in solutions of 154 mosM was greater than that in 310 mosM solutions, which was greater than the uptake in 616 mosM solutions, each by an average of 40-50%. Incorporation of drug into tumor cells was also assayed in vivo using a teratoma cell line propagated i.p. in mice. Tumor cell uptake of doxorubicin was increased to a similar extent when this drug was administered in hypotonic solutions of 154 mosM and was decreased by administration in hypertonic solutions of 465 mosM, as compared to solutions of 310 mosM. These results demonstrate that the uptake of chemotherapeutic agents into tumor cells is increased significantly when these drugs are infused in solutions of lower osmolalities, a finding which may be exploited in clinical situations.

On betaH-Leu5-endorphin and schizophrenia.

A previously unknown peptide, betaH-Leu5-endorphin, has been reported in the dialysates of schizophrenic patients. Accordingly, hemofiltrates from two schizophrenic and two control patients were examined for the presence of betaH-Leu5-endorphin. The opioid peptides were detected by a radioreceptor assay after separation and identification by gel filtration and high-performance liquid chromatography. With a detection limit of 30 pmole/L of hemofiltrate, no betaH-Leu5-endorphin or Met5-endorphin was found in controls or in patients. Whatever the possible involvement of endorphins in schizophrenic behavior, they are not present at detectable levels in the hemofiltrates of two well-characterized schizophrenic patients, thereby casting doubt on a general relationship of Leu-endorphin and schizophrenia.

Prolactin regulation of pim-1 expression: positive and negative promoter elements.

The lactogen-dependent rat Nb2 lymphoma is a useful model to investigate PRL signaling pathways that lead to regulation of gene transcription. A primary mechanism coupled to PRL receptor (PRLR) activation in Nb2 cells involves phosphorylation by Jak-family tyrosine kinases of one or more signal transducers and activators of transcription (Stat) factors which subsequently bind to gamma-interferon activation sequences (GAS) within promoter regions of target genes. However, it is presently unclear whether this mechanism is operative as a means for regulating PRL-induced gene expression to the exclusion of other signaling pathways. Previously, we reported that PRL directly stimulated rapid expression of the protooncogene, pim-1, at the mRNA and protein levels in lactogen-dependent Nb2-11 cells. In the present study, experiments were conducted to evaluate signaling mechanisms by which PRL regulates transcription of pim-1. Toward this end, a 1,268-bp segment upstream of the transcription initiation site of the 5'-pim-1 promoter and a series of deletion mutants were ligated upstream of the chloramphenicol acetylase transferase (CAT) gene in an expression vector that was introduced into FDC/Nb2 cells, a premyeloid line that stably expresses the intermediate form of the PRLR. Analysis of PRL-treated cultures indicated that two elements [distal (DE), -427 to -336 bp and proximal (PE), - 104 to -1] but not several GAS or GAS-like sequences were required for hormone activation of the pim-1 promoter. Moreover, treatment of Nb2-11 cells with PRL activated protein binding to these elements assessed by gel mobility shift assay. Deoxyribonuclease I (DNase I) protection experiments revealed a motif containing a nuclear factor-1 (NF-1, -224 to -217 bp) half-site that was hydrolyzed when exposed to extracts from PRL-treated cells but protected by proteins from unstimulated cells. Gel mobility shift analysis of this sequence showed decreased protein binding after PRL stimulation. It is concluded that the PRLR initiates pim-1 transcription by a mechanism that involves transcriptional activation by factors that stimulate the DE- and PE-sites and derepress a NF-1-containing element. Moreover, this mechanism appears to be independent of an interaction between Stat transcription factors and GAS-like elements present within the promoter.

Hypogeusia and zinc depletion in chronic dialysis patients.

Dialysis patients generally have a poor appetite, do not enjoy eating, and complain of food, particularly protein, as being disagreeable. Twenty dialysis patients with the above symptoms were tested for taste acuity, serum zinc (Zn), Zn concentrations in hair samples (intracellular Zn), and daily caloric intake. A double-blind, cross-over study was instituted using a Zn supplement and a placebo. After supplementation with Zn, taste acuity markedly improved in 95% of patients and Zn concentrations in hair increased in 85% of patients. The patients' appetites were improved; the average caloric intake increased by 675 kcal/day, and intolerance to protein diminished. In addition 10 normal control subjects were studied pre- and post-Zn supplementation for fasting blood glucose, serum Zn levels, and hair Zn concentration. Side effects were noted, and these usually correlated with elevated serum Zn levels and were minimized or disappeared with decrease in dosage or cessation of therapy.

Combined technological-clinical approach to wearable dialysis.

To evaluate the constraints imposed upon the design of wearable dialysis systems, prototypes using currently available hardware were applied to three different dialysis formats: 1) the wearable artificial kidney (WAK) for hemodialysis (HD), 2) reciprocating peritoneal dialysis (RPD), and 3) alternating sorbent based dialysis/diafiltration(Ds/F) with a highflux membrane. 1) WAK dialysis has undergone extensive clinical trials with results comparable to standard HD. This system, including a self-contained power source, weighs 4.5 kg. The pulsatile blood flow can be disadvantageous, and cost of disposables is high. 2) RPD is shown to be an effective PD format, with the clearance of urea averaging 29.7 (23.9 to 41.5) ml/min in 14 patients, totalling 548 RPD dialyses. 3) After four conceptual trials, the Ds/F system was used for one treatment. Mass transfer results show removal of: urea nitrogen, 15.4 g; creatinine, 1.9 g; uric acid, 1.2 g; potassium, 89.2 mEq; and a positive bicarbonate balance of 94 mEq. The design constraints of these systems were elucidated, and prototype compact delivery systems have been constructed. It is concluded that a) non-mechanical PD wearability exists and b) true wearability of HD or Ds/F systems is not yet technologically feasible, but constraints are less rigid for Ds/F than for HD.

Intravesical electromotive administration of drugs for treatment of superficial bladder cancer: a comparative Phase II study.

OBJECTIVES: To evaluate the efficacy of electromotive administration (EMDA) of intravesical mitomycin-C (MMC) in patients with superficial bladder tumors and to evaluate the toxicity of the treatment. METHODS: Thirteen patients with multifocal Stages Ta-T1 and G1-G2 transitional cell carcinoma (TCC) of the bladder, primary or recurrent (group A), received MMC 40 mg (retained in the bladder for 2 hours) once a week for 8 weeks. Fifteen patients with the same characteristics (group B) were treated with EMDA/MMC at a current of 15 mA for 20 minutes once a week for 8 weeks. All lesions in the bladder except one (marker) were resected in each patient. RESULTS: In group A, 5 of 12 patients (41.6%) demonstrated complete macroscopic and histologic disappearance of the marker lesion (complete response [CR]). In group B, 6 of 15 patients (40%) had a similar CR. Recurrence rate in responders was 60% in group A versus 33% in group B after 7.6 and 6 months, respectively. Disease-free interval was 14.5 months in the EMDA/MMC group compared to 10.5 months in the MMC group. Side effects were few. CONCLUSIONS: In intermediate risk patients with TCC of the bladder, EMDA/MMC was not superior to MMC alone with a CR rate of 41% versus 41.6%. In responders, a lower recurrence rate and a longer disease-free interval were observed in the EMDA/MMC group.

Iontophoretic delivery of morphine for postoperative analgesia.

Iontophoresis is a method of transdermal administration of ionized drugs in which electrically charged molecules are propelled through the skin by an external electrical field. This was a prospective, randomized, single-blind study to determine the effectiveness of iontophoretically delivered morphine HCl for the control of postoperative pain. Thirty-eight patients who underwent total knee or hip replacement completed this clinical trial. Informed consent was obtained before surgery and patients were instructed on the use of a patient-controlled analgesia (PCA) device. Postoperatively, pain in the recovery room was initially controlled with IV meperidine, and thereafter with PCA therapy using meperidine, 2 mg/cc, with a dose of 10 mg IV and a lock-out period of 15 min. The dose was adjusted as necessary and the lock-out period remained the same. The number of patient requests and the dose (mg) administered was recorded hourly. On the morning following surgery, iontophoresis devices were attached for 6 hr to patients who received either morphine HCl or lactated ringers solution. During this period and for 12 hr following completion of iontophoresis, PCA analgesia remained available to patients. Venous blood samples for determination of morphine levels were obtained every 30 min during iontophoresis, then every 60 min for 2 hr following iontophoresis. Of the 38 patients, 17 received iontophoresed morphine, and 21 received iontophoresed lactated ringers. The morphine group utilized the PCA device more than the control group during the baseline period. However, following the institution of iontophoresis and continuing up to 12 hr following completion of iontophoresis, the morphine group used significantly less PCA meperidine to maintain analgesia than the control group (p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Bladder and urethral anaesthesia with electromotive drug administration (EMDA): a technique for invasive endoscopic procedures.

OBJECTIVE: To assess the efficacy of the electromotive administration of lignocaine and adrenalin as local anaesthesia (EMDA/LA) for invasive lower urinary tract procedures. PATIENTS AND METHODS: Electric current generators, catheters and electrodes were designed and fabricated, using defined electrochemical principles, to carry out EMDA/LA of the bladder and prostatic urethra of 91 patients who underwent 27 bladder-mapping biopsies, 62 transurethral resections (TURs) of bladder tumours, 21 transurethral incisions on the prostate or bladder neck incisions, 12 TURs of the prostate (122 operations in total) and nine miscellaneous interventions, all using rigid instruments. Resections were performed using electrocautery. Most patients, while minimally sedated and fully conscious, completed an assessment of EMDA/LA using a simple pain scale. RESULTS: In five of the 122 procedures, the pain was described as intolerable, six were recorded as painful but tolerable and the remaining 111 procedures were recorded as having minimal to no discomfort only. Side-effects were few, there was no clinical evidence of lignocaine toxicity and serial serum lignocaine levels measured in four patients were innocuous. CONCLUSIONS: EMDA/LA provides safe, effective anaesthesia for most invasive endoscopic procedures in the lower urinary tract.

Potential novel methods for insulin administration: I. Iontophoresis.

It is theoretically feasible to administer an ionized solute transcutaneously using an electric current. Attempts by our group to administer conventional, regular (soluble) insulin to human volunteers by iontophoretic methods failed, probably because such insulin is only weakly ionized and much of it is present in the polymeric form. Animal experiments with pigs defined patterns of portal and systemic insulin concentrations for native insulin secretion, intraperitoneal injection of insulin, and peripheral (intramuscular) injection of insulin. Using a more strongly ionized and predominantly monomeric form of insulin, transcutaneous administration of this hormone by iontophoresis was demonstrated in an experimental animal.

Potential novel methods for insulin administration: II. Self-regulating internal drug delivery systems.

Several glycosylated insulins were synthesized and their binding constants to a lectin, Concanavalin A (Con A), as compared to that of glucose, were assessed. When Con A-glycosylated insulins were placed in fluids containing different concentrations of glucose, competitive displacement of glycosylated insulin occurred to a degree dependent upon the ambient concentration of glucose. As these glycosylated insulins possess a biological activity (80% of that of standard soluble insulin) such results demonstrate the beginnings of a "chemical" artificial beta cell.

The quantity and distribution of radiolabeled dexamethasone delivered to tissue by iontophoresis.

A pilot study was conducted in the first of two monkeys using either radiolabeled Dm-Na-P or radiolabeled hydrocortisone sodium succinate, together with lidocaine HCl. This study indicated an approximately tenfold increase in the quantity of Dm-Na-P delivered to the test electrodes (4 mA; 20 minutes) whereas the quantity of hydrocortisone delivered from the test electrodes was only marginally (approximately 10%) increased as compared with that from the controls. In terms of an anti-inflammatory activity, the effective dose of Dm-Na-P in all tissue layers underlying the test electrodes was at least tenfold that of the hydrocortisone. Therefore, further trials with hydrocortisone were abandoned. In the second animal, positive test electrodes (5 mA; 20 minutes, were sited over five joints on the right side of the body and matching control electrodes (0 mA; 20 minutes) were placed over corresponding joints on the left side of the body. The control and test electrodes each contained 1.0 ml tritium-labeled Dm-Na-P (approximately 4.0 mg) and 2.0 ml 4% lidocaine HCl (80 mg). Local tissue concentrations of Dm-Na-P were higher than those that would be obtained by systematic therapy and lower than would be obtained by local injection.

Electromotive drug administration of lidocaine to anesthetize the bladder before intravesical capsaicin.

PURPOSE: The discomfort caused by intravesical capsaicin during instillation may restrict its use in some patients. We studied the effectiveness of using electromotive drug administration (EMDA) of lidocaine to anesthetize the bladder before capsaicin. MATERIALS AND METHODS: EMDA of lidocaine and epinephrine was performed in 8 patients with detrusor hyperreflexia using catheters, electrodes and an electrical current generator (20 mA., 15 minutes) followed immediately by intravesical capsaicin (2 mmol./l.) for 30 minutes under urodynamic monitoring. The patients scored suprapubic pain at 5 minutes and at the end of the capsaicin instillations on a scale of 0 to 10. Of the 8 patients 5 had had previous capsaicin treatments and the scores were compared to previous scores when intravesical lidocaine without EMDA had been used as local anesthesia before capsaicin. RESULTS: The pain scores during capsaicin instillations after EMDA of lidocaine were much lower than those during capsaicin instillations after lidocaine alone. EMDA virtually eliminated the hyperreflexic contractions of the bladder occurring during capsaicin instillations, thus reducing the risk of urethral leakage, and prevented autonomic dysreflexia that had previously occurred in 1 patient. CONCLUSIONS: EMDA of lidocaine is an effective means of reducing pain during subsequent intravesical capsaicin, which makes the use of capsaicin in the treatment of detrusor hyperreflexia more acceptable.

Painless cauterization of spider veins with the use of iontophoretic local anesthesia.

Treatment of small vascular abnormalities of the skin is painful, and injections of local anesthetic agents distort the operating field. Iontophoresis of salt-free, 4% lidocaine, with and without epinephrine, delivered to the skin from a receptacle with a semipermeable membrane, and with the use of a current-controlled electrical system, resulted in effective anesthesia of the skin for cauterization of "spider" veins. Fourteen subjects received 32 treatments. Sixteen paired areas of spider veins were anesthetized with iontophoresis of lidocaine and with lidocaine plus epinephrine 1/50,000. The duration of anesthesia with lidocaine averaged 14 minutes; relief of pain was complete in 9/16 treatments, adequate in 6/16, and inadequate in 1/16. Lidocaine plus epinephrine supplied anesthesia for 56 minutes; relief of pain was total in 14/16 treatments and adequate in the remaining two. Thus iontophoresis with the use of selected local anesthetic and iontophoretic equipment provides adequate conditions for cauterization of spider veins, a procedure poorly served by conventional local anesthesia.

Intravesical electromotive drug administration for the treatment of non-infectious chronic cystitis.

Seventeen patients with non-infectious chronic cystitis (NICC) (9 with interstitial cystitis, 6 patients with radiation cystitis, 1 with chemocystitis and 1 with lupoid cystitis) were treated with electromotive administration of intravesical lidocaine and dexamethasone followed by hydrodistension of the bladder. Complete resolution of symptoms for an average of 7.5 months was observed in 11 patients (65%), partial improvement in 4 (23.5%). In this series no complications occurred. Electromotive drug administration (EMDA) and cystodistension were well tolerated by all patients. The treatment was performed on an outpatient basis, thus reducing therapeutic costs. The results presented demonstrate that the combination of EMDA and bladder hydrodistension is an effective first-line treatment for NICC patients.

Iontophoretic administration of lidocaine anesthesia in office practice. An appraisal.

BACKGROUND: Obtaining anesthesia for dermatologic, office-based surgeries often involves the pain of needle stick and burning upon injection of local anesthetic agents. No truly effective method for obtaining painless anesthesia is well accepted in the United States. OBJECTIVE: A study was carried out using iontophoresis of lidocaine with epinephrine to determine the practicality of this method of delivering local anesthesia prior to invasive procedures in dermatology offices. METHODS: A two-center, open-label study was undertaken using iontophoretic administration of 4% lidocaine with epinephrine 1:50,000 before painful procedures occurring in the dermatologists' office. RESULTS: Ninety-four procedures in 64 patients were evaluated. Both patients and physicians recorded 51% of procedures as painless, 36% as minor (partial), and 14% causing moderate to severe pain. Iontophoretic local anesthesia was 80 to 100% effective for pain relief for injections, abrasions, laser surgery, and cautery; it was significantly less effective in effecting pain relief for dermal excisions. CONCLUSIONS: Iontophoretic administration of anesthesia is a useful adjunct to the armamentarium of dermatologists performing surgical procedures in their office.

Dialysis/hemofiltration in schizophrenia: a journey by night and cloud.

Hypotheses for the etiology of schizophrenia are discussed and related to possible treatments utilizing artificial kidney systems. For hemofiltration particularly, a theoretical framework is presented for treatment planning. Emphasis is placed on the necessity of using rigid diagnostic criteria for patient selection. Results are reported on two "strict" schizophrenic patients after a series of hemofiltration treatments. One patient showed no clinical improvement after seventeen treatments and died subsequently in a mountaineering accident. Though clinical improvement was noted in the second patient (22 treatments in four months), it is unjustifiable to attribute this solely to hemofiltration. Increased family and medical staff attention towards the patient is sufficient explanation for all changes noted in the patient's symptomatology. Chemical analyses so far have failed to detect any endorphins, normal or abnormal, in the hemofiltrates of either the two patients or two normal controls (sensitivity 30 pmol/L).

Lidocaine anesthesia: comparison of iontophoresis, injection, and swabbing.

The duration and depth of anesthesia produced by lidocaine with three methods of administration were studied. To test duration of anesthesia, either lidocaine or placebo was administered by iontophoresis, subcutaneous infiltration, or swabbing to each of three sites 3 cm apart on the flexor surface of each forearm of 27 subjects. To test for feeling, the tip of a 21-gauge hypodermic needle was pressed on each application site every five minutes until feeling returned. The depth of anesthesia achieved with iontophoresis or infiltration of lidocaine was tested on the flexor surface of each forearm of 12 subjects, with a random assignment of application methods to each arm. Lidocaine iontophoresis produced local anesthesia of significantly longer duration (p less than 0.001) than topical application of lidocaine or placebo by any route of administration, but of significatnly shorter duration (p less tahn 0.001) than lidocaine infiltration. The results showed that lidocaine iontophoresis is an effective method of producing local anesthesia for about five minutes without requiring the use of a hypodermic needle and syringe.