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PubMed1995

WENDEC: a deconvolution program for processing hormone time-series.

The estimation of the glandular secretory rate from time-series of hormone concentration in plasma can be formulated as a deconvolution problem. In particular, the paper addresses the analysis of frequently sampled data collected in order to study spontaneous pulsatile secretion. Standard deconvolution methods do not allow for the non-negativity constraint and the presence of high-frequency components in the secretory rate. In order to overcome the intrinsic ill-conditioning of the problem, the maximum entropy method is used to obtain a probabilistic representation of the prior knowledge concerning the unknown secretory signal, thus leading to a White Exponential Noise (WEN) model. The deconvolution problem is then posed within a Bayesian framework and solved by means of Maximum-A-Posteriori estimation. The program that implements the algorithm handles non-negativity constraints, provides confidence intervals, and is computationally and memory efficient.

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PubMed1994

Effects of lisinopril and nitroglycerin on blood pressure early after myocardial infarction: the GISSI-3 pilot study.

OBJECTIVES: To evaluate the safety in terms of hypotensive action of nitroglycerin and lisinopril started early after myocardial infarction. PATIENTS AND METHODS: One thousand five hundred twenty-six patients with suspected myocardial infarction were randomized by 174 centers within 24 hours from the onset of symptoms to receive oral lisinopril (5 then 10 mg/day), nitroglycerin (intravenous infusion during the first 24 hours, then 10 mg/day transdermal), or neither. RESULTS: Systolic blood pressure, intensively monitored during the first 72 hours, decreased sharply by 11 mm Hg during the first 2 hours, then more slowly to an average value of 120 mm Hg. Nitroglycerin lowered systolic blood pressure during the first 24 hours by 2.7 mm Hg versus control subjects, and it was similar to control subjects from 24 hours. Lisinopril reduced systolic blood pressure by 4.2 mm Hg over 72 hours compared with control subjects. Persistent hypotension was significantly more frequent in the lisinopril group (21.4%) than in the nitroglycerin group (10.9%) or control group (9.8%), but absolute numbers of deaths in patients with persistent hypotension were almost identical. CONCLUSIONS: Lisinopril and nitroglycerin are both safe and effective in reducing blood pressure in the first day after myocardial infarction. However, the effect is lost thereafter with transdermal nitroglycerin, but persists with lisinopril.

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