The pharmacokinetics of morphine and morphine glucuronides in kidney failure

The pharmacokinetics of morphine and its glucuronide metabolites were investigated in three groups of patients with kidney failure (nondialyzed, receiving dialysis, and transplantation) and compared with a group of normal healthy volunteers. Patients in all three renal groups were undergoing surgical procedures (nondialyzed group undergoing arteriovenous fistula formation, dialysis group undergoing placement of a peritoneal dialysis catheter, and the transplant group undergoing live donor kidney transplant). A sensitive, specific high-performance liquid chromatographic assay was used to quantitate morphine, morphine-3-glucuronide, and morphine-6-glucuronide. Patients with kidney failure had a significantly increased morphine area under the curve (AUC) compared with control subjects. There was also an increase in the metabolites morphine-3-glucuronide and morphine-6-glucuronide that was severalfold greater than the increase in morphine AUC. This metabolite accumulation was reversed by kidney transplantation, providing an elegant confirmation on the role of the kidney in morphine pharmacology.

Enhancement after feline immunodeficiency virus vaccination

Cats were vaccinated with one of the three preparations: purified feline immunodeficiency virus (FIV) incorporated into immune stimulating complexes (ISCOMs), recombinant FIV p24 ISCOMs, or a fixed, inactivated cell vaccine in quil A. Cats inoculated with the FIV ISCOMs or the recombinant p24 ISCOMs developed high titres of antibodies against the core protein p24 but had no detectable antibodies against the env protein gp120 or virus neutralising antibodies. In contrast, all of the cats inoculated with the fixed, inactivated cell vaccine developed anti-env antibodies and four of five had detectable levels of neutralising antibody. However, none of the vaccinated cats were protected from infection after intraperitoneal challenge with 20 infectious units of FIV. Indeed there appeared to be enhancement of infection after vaccination as the vaccinated cats become viraemic sooner than the unvaccinated controls, and 100% of the vaccinated cats became viraemic compared with 78% of the controls. The mechanism responsible for this enhancement remains unknown.

Intraperitoneal therapy of malignant ascites associated with carcinoma of ovary and breast using radioiodinated monoclonal antibody 2G3

A phase I/II study of intraperitoneal (ip) radioimmunotherapy was conducted in ovarian or breast cancer patients with symptomatic chemotherapy-resistant ascites using a novel anti-mucin monoclonal antibody (mAb) 2G3 labeled with 131I. Tracer doses of 2 mCi [131I]2G3 were given by ip injection to 11 patients, followed by increasing therapeutic doses up to 150 mCi (cumulative) in 9 patients. There was no serious toxicity. Temporary palliation of ascites was observed in 3 of 4 patients who received doses greater than 50 mCi. Total body elimination half-life of the radiolabeled antibody assessed by gamma scintigraphy ranged from 95 to 250 hr, longer than data previously reported in patients without ascites treated with ip administered radiolabeled antibodies. However, uptake of radiolabel by tumor nodules was small and variable (2 x 10(-4) - 2 x 10(-2) % ID/g), and preferential uptake by tumor compared to normal peritoneum was observed in only 2 of 5 patients in whom biopsies were obtained. These results suggest that the observed palliation of ascites is due to prolonged retention of radiolabeled antibody in the peritoneal cavity even in the absence of specific targeting.

A sensitive assay for detection and measurement of neutralising antibody to human immunodeficiency virus

An assay based on the inhibition of syncytium formation in C8166 cells was developed to measure low levels of neutralising antibody (NT-AB) to human immunodeficiency virus (HIV) and to detect cross-reactivity between virus strains. The relationship between virus challenge and antibody titre was represented by a tripartite curve which was essentially linear over moderate levels of virus input. Based on these findings, antibody titres were standardised against 100 TCID50 of challenge virus. However, lower virus inocula were found to detect minimum levels of antibody. Reproducibility of antibody titres between tests was high, with variation generally lying within one dilution step. The improved sensitivity of the technique allowed detection of NT-ABs in animals immunised with immune-stimulating complexes (ISCOMS) incorporating HIV antigens. Consistent levels of cross-reactivity between HIV strains was demonstrated, indicating the presence of distinct viral groups, from which dominant isolates may be chosen for use in vaccination studies.

The analgesic activity of morphine-6-glucuronide

1. The pharmacokinetics, cardio-respiratory effects and analgesic effects of intravenous morphine-6-glucuronide were studied in 20 cancer patients with pain. Four different dose levels (0.5, 1, 2, and 4 mg 70 kg-1) were studied. Plasma concentrations of morphine-6-glucuronide were measured for 12 h after dosing. Pulse rate, respiratory rate and blood pressure were monitored, and pain relief was measured using two rating scales and a visual analogue scale. 2. The mean elimination half-life (+/- s.d.) of morphine-6-glucuronide was 3.2 +/- 1.6 h. The mean AUC standardised to a dose of 1 mg 70 kg-1 was 390 +/- 263 nmol l-1 h. Mean morphine-6-glucuronide clearance was 96 +/- 38 ml min-1. There was a direct relationship between morphine-6-glucuronide plasma clearance and calculated creatinine clearance (r = 0.81, P less than 0.001). 38 +/- 22% of the dose of morphine-6-glucuronide was recovered unchanged in the urine in 24 h. No morphine or morphine-3-glucuronide was detected in the plasma or urine of any patient after morphine-6-glucuronide treatment. 3. Morphine-6-glucuronide exerted a useful analgesic effect in 17/19 assessable patients for periods ranging between 2 and 24 h. No correlation was observed between dose or plasma morphine-6-glucuronide concentrations, and duration or degree of analgesia. No clinically significant changes in cardio-respiratory parameters were observed. No patients reported sedation or euphoria. Nausea and vomiting were notably absent in all cases. 4. Morphine-6-glucuronide is an effective and well-tolerated analgesic. It is likely that the majority of the therapeutic benefit of morphine is mediated by morphine-6-glucuronide.(ABSTRACT TRUNCATED AT 250 WORDS)

Incorporation of soluble antigens into ISCOMs: HIV gp120 ISCOMs induce virus neutralizing antibodies

Through a process of covalent attachment of palmitic acid, we have incorporated recombinant gp120 of HIV strain IIIB into ISCOMs. Rabbits immunized with ISCOMs incorporating 10 micrograms gp120 produced high levels of gp120-specific antibody, comparable to the response to ten times as much antigen in complete Freund's adjuvant. The ISCOM-induced antisera showed virus neutralizing activity against the homologous strain, but failed to neutralize two heterologous strains of HIV-1. The antisera recognized non-conformationally determined epitopes on gp120, and antibody binding to gp120 was affected by glycosylation of the viral glycoprotein.

Changing concepts in the management of vulvar cancer

Vulvar carcinoma varies widely in its clinical presentations and prognosis. The reviewed literature outlines the achievements of conventional surgery, radiation, or chemoradiation therapy in its management. Currently therapeutic concepts are evolving. New treatment strategies replacing the uniform use of radical vulvectomy and bilateral groin dissection are proposed. These strategies are tailored to the clinical and pathological disease extent and location and integrate the possible therapeutic advantages of both surgery and chemoradiation. The testing and use of the proposed multimodality therapy protocols require the expertise of gynecologic, radiation, and medical oncologists. This approach should lead to improved anatomic and functional preservation in early disease and improved locoregional in advanced disease.

Phase II trial of UFT in advanced colorectal and gastric cancer

A phase II trial of continuous oral therapy with UFT, a combination of uracil and the 5-fluorouracil analogue 1-(2-tetrahydrofuryl)-5-fluorouracil (Futraful, Ftorafur), was conducted in 40 patients with advanced colorectal cancer and 18 patients with advanced gastric cancer. Six partial responses were seen in the 36 evaluable patients with colorectal cancer (response rate 16.6%; 95% confidence limits 6.4-32.8%), and one partial response was seen in the 16 evaluable patients with gastric cancer (response rate 6%; 95% confidence limits 0.27-30.2%). The overall toxicity of the treatment was low, and all patients were treated as outpatients. The results suggest that oral UFT has comparable activity to standard regimes of 5-fluorouracil, and because of the convenience of oral administration is a useful therapy in the management of patients with advanced colorectal cancer.

Roz osborne on the support for the student bill of rights

The Nursing Students Bill of Rights (NSBR) is probably one of the most discussed documents ever produced by the RCN. Since the RCN Council approved the second edition of the NSBR earlier this year, the discussion and criticism continue.

Morphine and metabolite behavior after different routes of morphine administration: demonstration of the importance of the active metabolite morphine-6-glucuronide

The pharmacokinetic parameters of morphine, morphine-6-glucuronide, and morphine-3-glucuronide were studied after single-dose morphine administration by five different routes. The quantitative significance of the active metabolite morphine-6-glucuronide was assessed, and the effects of novel dosing forms on morphine metabolism and distribution were examined. After administration of intravenous morphine the morphine-6-glucuronide plasma AUC exceeded that of morphine. After administration of oral morphine very low morphine levels were observed--the morphine-6-glucuronide plasma AUC exceeded that of morphine by a factor of 9:1. Sublingual, buccal, and sustained-release buccal morphine tablet administration resulted in delayed absorption, with attenuation and delay of peak morphine and metabolite levels. Morphine bioavailability and morphine glucuronide production were not altered.

Risk assessment initiatives for noncancer endpoints: implications for risk characterization of chemical mixtures

Current methods employed in risk assessment for noncarcinogens are associated with the estimation of reference doses (RfDs). These strategies reflect (appropriately) a protective philosophy in both theory and practice. The approaches are limited, however, in terms of the ability to project the likelihood of specific hazard above the reference dose and to integrate the health hazards of exposure to chemical mixtures (including both cancer and noncancer endpoints). Ongoing efforts that address guidelines for risk assessment of non-carcinogens, both singly and as components of mixtures, are presented. Included is a description of the range of potential biological response categories and associated parallel issues of adversity and severity. For example, the progression of histopathological change, organ system dysfunction and organismal disability is examined as it may affect risk characterization of mixtures. Mechanistic principles are suggested as an appropriate focus to systematically evaluate this progression. Once established, these principles may provide a reasonable framework in which to more accurately characterize risks associated with chemical mixtures.

Concurrent radiation and chemotherapy in vulvar carcinoma

Between June 1984 and February 1988 the role of radiation with concurrent infusional 5-fluorouracil with or without mitomycin C (CT-RT) was examined in 33 patients with vulvar cancer. The median duration of follow-up is 16 months (range 5 to 45 months). Nine received adjuvant postsurgical CT-RT and none has relapsed in the radiation field. Seven are alive disease free. Two have died of distant metastases. Of the 9 receiving definitive primary CT-RT, 6 had initial complete response with subsequent vulvar relapse developing in 3. Seven of the 9 remain disease free after CT-RT alone (in 3) or with the addition of a local excision of residual or recurrent disease (in 6). One patient did not respond to CT-RT and required a radical vulvectomy and groin node dissection. Fifteen received CT-RT for disease recurrence following primary surgery. Disease was present in the vulva only in 11, vulva and inguinal nodes in 1 and nodes only in 3. Eight of the 15 had a complete response and no relapses occurred in the treated sites. Four of the 8 dying of disease developed pulmonary metastases. Serious late complications developed in 2 patients, 1 avascular hip necrosis and 1 proctitis requiring a defunctioning colostomy. CT-RT appears tolerable and may contribute to enhanced locoregional control in recurrent or advanced disease. As initial therapy it may allow lesser surgery with preservation of normal anatomy in selected primary vulvar cancers.