[Neonatal localized neuroblastoma: 52 cases treated from 1990 to 1999].

Unlabelled: Neuroblastoma is the most frequent tumor observed in the newborn. The aim of this study was to review clinical features, treatment and outcome of newborns diagnosed with a localized neuroblastoma.

Population And Methods: Data from 52 cases treated according to the NBL 90 and 94 protocols between 1990 and 1999 in 18 French centers of pediatric oncology were analyzed.

Species comparison of adenosine A1 receptors in isolated mammalian atrial and ventricular myocardium.

Various species have been used as models to study the effects of adenosine (ADO) on atrial and ventricular myocardium, but few direct tissue comparisons between species have been made. This study further characterizes adenosine A(1) receptor binding, adenylate cyclase activity and direct and indirect A(1) receptor-mediated functional activity in atrial and ventricular tissue from Sprague-Dawley rats and Hartley guinea pigs. Rat right atria (RA) were found to be significantly more sensitive to cyclopentyladenosine (CPA), while guinea pig left atria (LA) were more sensitive to CPA.

[Neonatal withdrawal syndrome in twins born to a mother on methadone substitution].

We report the cases of two female twins whose mother was taking methadone substitution therapy. These cases demonstrate the unpredictable nature of the neonatal withdrawal syndrome. One baby developed signs of withdrawal late 10 days after birth.

Effects of cyclopentyladenosine on isoproterenol response in adult and senescent cardiac tissue from Fischer 344 rats.

To characterize age-related changes in beta-adrenergic responsiveness and to test the hypothesis that an increase in the effects of adenosine contribute to impaired beta-adrenergic responsiveness, Fischer 344 rat right atria (RA), left atria (LA), and left ventricular trabeculae carnae were exposed to the beta-receptor agonist isoproterenol (ISO), followed by four doses of the selective adenosine A(1) receptor agonist cyclopentyladenosine (CPA). Spontaneous contractile rates of adult RA were inhibited more than senescent RA by CPA. Contractility (+dF/dt) of adult LA was reduced more than senescent LA by CPA.

[Management of drug addict pregnant women and their children].

Children of substance abuse mothers have an increased risk of severe pathological disorders such as perinatal diseases (prematurity, intrauterine growth retardation, infections) with their neurological and respiratory complications and sequelae, and transmission of drug addiction related infections, ie human immunodeficiency virus, hepatitis B and C virus, syphilis. Many of these children present a drug withdrawal syndrome characterized by restlessness and jetteriness during the neonatal period. This is frequently followed by a post withdrawal period of several weeks duration with crying, excitement, sleep and feeding difficulties.

[Medical-social outcome of 59 infants born to addicted mothers].

Background: Follow up of children born to drug-addicted mothers is difficult because of social context. The aim of this study was to determine the precise outcome in a cohort of infants from two neonatal units. POPULATION AND METHODS; Analysis of perinatal and follow up data of 59 infants born to drug-addicted mothers, admitted from 1988 to 1993 in the neonatal units of Colombes and Neuilly.

Age-related characterization of atrial adenosine A1 receptor activation: direct effects on chronotropic and inotropic function in the Fischer 344 rat.

Adenosine, an endogenously produced nucleoside, has direct negative chronotropic and inotropic effects on right and left atrial tissues, respectively. Age-related differences in the effects of A1 adenosine receptor activation on atrial rhythmic and contractile function were investigated in adult (6-8 months) and senescent (23-24 months) Fischer 344 (F344) rats. Senescent right atria (RA) were more sensitive to the negative chronotropic effects of R-phenylisopropyladenosine (R-PIA), a selective A1 receptor agonist, than adult RA (EC50: 4.

Age-related effects in rabbit hearts of N6-R-phenylisopropyladenosine, an adenosine A1 receptor agonist.

Interventions known to increase cytoplasmic Ca2+ appear to amplify age-related impairment of cardiac function. In addition, increased release of interstitial adenosine, an endogenous nucleoside, has been suggested to mediate the diminished beta-adrenergic responsiveness in senescent heart. However, the direct effects of adenosine A1 receptor activation on senescent myocardium have not been investigated thoroughly.

Cardiac functional responses to adenosine by PD 81,723, an allosteric enhancer of the adenosine A1 receptor.

Adenosine, a locally released and rapidly metabolized nucleoside, protects the heart from damage during ischemia by reducing oxygen demand and increasing oxygen supply. The aminothiophene derivative (2-amino-4,5-dimethylthien-3-yl)[3-(trifluoromethyl)phenyl]-met hanone (PD 81,723) has been shown to act as an allosteric enhancer of the adenosine A1 receptor in brain membranes and thyroid cells. The present study investigates the effects of PD 81,723 in spontaneously contracting right atria and electrically stimulated left atria isolated from Sprague-Dawley rats.

Overcoming problems with polypharmacy and drug misuse in the elderly.

Polypharmacy, the inappropriate use of multiple drug regimens, has a significant impact on the health of elderly individuals. Drug use increases with age, but suitability of therapy is sometimes difficult to define. In ambulatory and hospital care, there is some documentation of poor prescribing practices by physicians and drug misuse by patients.

Calcium antagonists in geriatric patients: diltiazem in elderly persons with hypertension.

Pharmacodynamics and disposition of diltiazem were determined in twelve young (30 to 39 years of age) and twelve elderly (65 to 83 years of age) persons with hypertension after they had received diltiazem by rapid intravenous and long-term oral administration. Plasma disappearance half-life of diltiazem increased similarly and significantly in both groups with long-term dosing (young: rapid intravenous, 3.7 +/- 0.

Physiological response to isoproterenol and coupling of beta-adrenergic receptors in young and elderly human subjects.

Diminished adrenergic responsiveness occurs in aged humans. The purpose of this study was to evaluate the coupling of beta-adrenergic receptors from human neutrophil preparations, and to investigate the relationship of this biochemical parameter to heart rate response after isoproterenol administration in young and elderly individuals. Fifteen young (aged 23-39 years) and eleven elderly (aged 59-82 years) volunteers participated in the study.

Acute and chronic studies of diltiazem in elderly versus young hypertensive patients.

The pharmacodynamics, disposition and hormonal responses to acute intravenous and chronic oral diltiazem treatment were compared in young and elderly hypertensive patients. In elderly patients, supine diastolic blood pressure decreased significantly during the first week of treatment (baseline mean +/- standard error of the mean, 100 +/- 1 to 93 +/- 2 mm Hg) and decreased further during the study to 86 +/- 2 mm Hg at the end of the study. Diastolic blood pressure of the young patients decreased significantly by the third week of treatment (from 104 +/- 2 to 97 +/- 3 mm Hg) and decreased further during the study to 94 +/- 2 mm Hg at the end of the study.

N-monodesmethyldiltiazem is the predominant metabolite of diltiazem in the plasma of young and elderly hypertensives.

1 Twelve young (ages 30-39 years) and twelve elderly (ages 65-83 years) hypertensives were administered diltiazem twice daily for 2 weeks at doses up to 240 mg day-1. 2 Plasma was analysed for diltiazem, N-monodesmethyldiltiazem, and desacetyldiltiazem concentrations after a single 10 min intravenous infusion of 21.8 mg diltiazem HCl on day 1 and after the morning oral dose of 120 mg diltiazem base on day 14.