A comparison of the inactive urinary kallikrein:creatinine ratio and the angiotensin sensitivity test for the prediction of pre-eclampsia

Objective To determine the relation between the inactive urinary kallikreimcreatinine ratio (IUK:Cr) and the angiotensin sensitivity test (AST) at 28 weeks of gestation and to assess each as a screening test for pre-eclampsia.
Design Prospective interventional study.
Subjects Four hundred and fifty-nine normotensive nulliparous women recruited from hospital antenatal clinics.
Setting John Radcliffe Maternity Hospital, Oxford, and Queen Charlotte's and Chelsea Hospital, London.
Interventions A urine sample for IUK:Cr measurement was provided before performing the AST at 28 weeks of gestation. Those women who demonstrated increased sensitivity to angiotensin II were entered into a randomised placebo controlled trial of low dose aspirin for the prevention of pre-eclampsia (CLASP).
Main outcome measures The development of pre-eclampsia.
Results The IUK:Cr ratio was significantly lower in those women who showed increased sensitivity to angiotensin II (   P < 0.0001  Student's t test). The sensitivity and specificity for detecting pre-eclampsia were, respectively, 22% and 85% for the AST and 67% and 75% for the IUK:Cr. Low-dose aspirin (60 mg) had no effect on the pregnancy outcome.
Conclusion There appears to be some relation between the IUK:Cr and AST tests in pregnancy. However, in this population, the IUK:Cr ratio was a better screening test for pre-eclampsia than the AST, but overall neither test was a powerful predictor for the syndrome.     

Process measures in an antenatal smoking cessation trial: another part of the picture

Data on provider and patient compliance can be crucial in understanding the degree of a health education program's effectiveness, as well as in identifying areas where the program requires modification. However, such data are rarely systematically reported in randomized trials. This report assesses the degree to which doctors and midwives complied with intervention protocols in a hospital antenatal smoking cessation trial, and also examines the program's acceptability to patients. Provider compliance was assessed principally via consultation audiotapes and provider-completed checklists. The audiotape analysis identified substantial compliance problems. For example, in relation to six specific smoking-related pregnancy risks, the proportions of Experimental Women informed about each individual risk ranged from 26 to 38% and the proportions receiving counselling items ranged from 52 to 79%. Doctors only informed a minority of Experimental Women of the increased risk of Sudden Infant Death Syndrome (28%) and of the presence of toxic chemicals in tobacco (21%). Comparison of compliance data from audiotapes and provider checklists revealed there was no significant agreement in three of four cases tested. Experimental Patients completed questionnaires to assess recall of smoking advice and to rate 12 program features. Of specific Experimental Program elements, the videotape (85%) received the highest level of positive patient ratings and the lottery (42%) the lowest. The process evaluation indicated that the Experimental Program needed some modification to increase its suitability for routine application. The findings also support the value of including an objective measure of provider compliance.     

Weekly 1-hour infusion of paclitaxel. Clinical feasibility and efficacy in patients with hormone-refractory prostate carcinoma

BACKGROUND: Preclinically, paclitaxel given according to an intense bolus schedule has significant antitumor activity against human prostate carcinoma cell lines in SCID mice. The authors evaluated the feasibility and efficacy of weekly 1-hour infusion of paclitaxel in patients with metastatic hormone-refractory prostate carcinoma (HRPC). METHODS: A total of 18 patients with progressive metastatic HRPC were enrolled. Patients had to have no prior chemotherapy. Paclitaxel was infused weekly at a dose of 150 mg/m(2) over 1 hour for 6 weeks every 8 weeks. RESULTS: Eighteen patients with a median age of 68.5 years and a median prostate specific antigen (PSA) level of 82 ng/mL (range, 2.17-3196 ng/mL) were enrolled. The median number of prior hormone treatments was 2, and 12 patients on antiandrogens completed antiandrogen withdrawal. Ten of eighteen patients had bone-only metastasis and eight had metastasis to bone with lymph node and/or visceral metastasis. Seventeen patients received a total of 31 cycles (157 courses) and 1 patient refused chemotherapy. All patients were included in response evaluation. Of the 8 [corrected] patients with measurable disease, 4 achieved a major response, with 1 complete response (in the lung) and 3 partial responses (1 in the liver and 2 in the lymph nodes). Seven of eighteen patients (39%) had a PSA decline of >/=50%. The major high grade toxicity was peripheral neuropathy, with 6 patients (35%) developing Grade 3 toxicity. CONCLUSIONS: Weekly 1-hour paclitaxel has activity in patients with HRPC. The major toxicity is peripheral neuropathy. The minimal myelosuppressive effects make a modified schedule (lower doses on the same schedule or a shorter schedule of the same dose) attractive for future combination chemotherapy trials.     

Maternal 3;13 chromosome insertion, with severe pre-eclampsia

A previously healthy young primigravida suffered very severe pre-eclampsia and was delivered at 32 weeks gestation. The baby was growth retarded with dysmorphic features, and died aged 4 days. Chromosome analysis of the baby revealed partial trisomy 13 resulting from recombination within a maternal insertion of part of 13q into 3p. To date, the maternal insertion has been identified in a further three members of the family and may have contributed to a number of spontaneous abortions, stillbirths and neonatal deaths in other family members. The various possibilities for recombination and malsegregation are discussed. An association between pre-eclampsia and trisomy 13 has been reported previously. To our knowledge this present paper constitutes the first report of partial trisomy for 13q occurring with pre-eclampsia.     

Theory and operation of a single microelectrode voltage clamp

The theory of operation of a discontinuous single-electrode voltage clamp using an ideal microelectrode (infinite response speed) and fixed (current-passing) duty cycle has been previously described. In this paper, the theory is extended by considering a microelectrode which has a finite response speed, by allowing the duty cycle to be variable, and by considering the clamp noise. Formulate are derived for the relationships between the step response, the steady-state error, the steady-state ripple, and the stability, in terms of the cycling frequency, the duty cycle, the open loop gain, and the electrical resistance and capacitance of the microelectrode and the cell membrane. In addition, the amplification of the microelectrode noise by aliasing is analysed, the error due to incomplete decay of the microelectrode voltage is described, and the accuracy of averaging the peak current measurement is established. To achieve the fastest dynamic response and the smallest steady-state error, the cycling period should be made as small as possible, and the open-loop gain should be as large as possible, consistent with stability. Incomplete decay of the microelectrode voltage destabilizes the clamp, and can introduce a significant clamp error. The choice of duty cycle is a compromise between reducing the noise and the step response time while avoiding design problems in the current output circuit. The output noise is amplified by aliasing. It can be minimized for a given output filter cutoff frequency by keeping the cycling frequency as high as possible, and by the use of an anti-aliasing filter whose cutoff frequency must be set for each microelectrode.