Search PubMed⌕ Search

Biomedical subjects

G Koren

Publications and source records attributed to G Koren.

At least 271 records · Page 15Linked to original sources
PubMed1997

Pregnancy outcome and neurodevelopment of children exposed in utero to psychoactive drugs: the Motherisk experience.

This paper presents an overview of the Motherisk Program data on pregnancy outcome and neurodevelopment of children exposed in utero to selected psychoactive drugs. First, the use of cocaine during pregnancy has been associated with increased risk of spontaneous abortions, abruptio placenta, premature labor, and stillbirth. Twenty-three adopted children exposed in utero to cocaine demonstrated an 8-fold increase in risk for microcephaly compared with controls. Global intelligence quotients (IQ) did not differ between the 2 groups, but the cocaine-exposed children achieved significantly lower scores on the Reynell language test. Second, the long-term neurobehavioral effects of fetal alcohol syndrome (FAS) were studied in 384 children to show that alcohol-induced brain insults, which consist of attention and memory deficits together, and poor adaptability and organization are not attenuated with age. Third, the rates of major malformations in children exposed in utero to fluoxetine, tricyclic antidepressants, and nonteratogenic drugs did not differ or exceed the expected rates in the general population. A 2nd phase of this study established the safety of antidepressants during pregnancy by demonstrating that the mean IQ and language scores are comparable in the 3 groups. A level 2 ultrasonography is recommended in cases of in utero exposure to lithium and carbamazepine because of an increased risk of cardiac malformations and spina bifida, respectively.

Developmental Disabilities↗
PubMed1997

Acute iron intoxication: significant differences between sexes.

Iron, one of the common medications in use among children and adults, is the leading cause of pediatric unintentional ingestion fatalities and is not an uncommon poisoning among adults. Accidental ingestion is common because iron-containing compounds are readily available, brightly colored, often sugar coated, and frequently considered harmless vitamins. There are no data on differences between sexes with regard to iron intoxication, and the management of iron overdose is the same for females and males. After oral administration by gavage of the LD50 of iron to Wistar rats, the pharmacokinetics of iron, baseline and peak serum iron levels, and mortality rates were compared between sexes. Prepubertal females died significantly more than males (p < 0.01), pubertal females died significantly earlier than males (p < 0.04), and the same was true among adult rats (p = 0.02). Baseline serum iron levels were not significantly different between prepubertal female and male rats, but female pubertal rats had significantly higher baseline iron levels than males (p = 0.006). After iron administration, females had significantly higher peak serum iron concentrations (p < 0.03). Mechanisms of iron absorption are still not completely known and, probably, there are differences in iron absorption between sexes, which may account for the differences in serum iron levels and mortality rates. While the therapeutic approach in cases of intoxication is individual, iron intoxication, as may be true for other poisonings also, treatments administered to females may need to be different from that given to males.

Administration, Oral↗
PubMed1997

The digoxin-propafenone interaction: characterization of a mechanism using renal tubular cell monolayers.

When propafenone is given with digoxin, digoxin serum concentrations increase. Although the digoxin-propafenone interaction is well known clinically, the mechanism by which propafenone interferes with digoxin elimination is unclear. To test the hypothesis that propafenone or one or both of its two major metabolites, 5-hydroxypropafenone (5-OHP) and N-depropylpropafenone (NDPP), inhibit the P-glycoprotein-mediated net renal tubular secretion of digoxin, we examined the transport of digoxin and the well-studied P-glycoprotein substrate vinblastine across confluent Madin-Darby canine kidney cell monolayers in the absence and presence of propafenone, 5-OHP and NDPP. Propafenone and its two major metabolites significantly inhibit the secretory flux of digoxin and vinblastine (propafenone > 5-OHP >> NDPP). Despite decreases in net transport, cellular digoxin accumulation did not decrease, suggesting that neither propafenone nor its metabolites prohibited digoxin from entering the cells at the basolateral side. NDPP, but not 5-OHP, was detected after 48 hr of incubation of the cells with propafenone alone. When the cells were incubated with propafenone or 5-OHP, apical accumulation of 5-OHP, but neither propafenone nor NDPP, against a concentration gradient was observed. These findings are consistent with the hypothesis that the digoxin-propafenone interaction results from the inhibition of the renal tubular transport of digoxin by propafenone and its metabolites. Our data suggest that propafenone is an inhibitor of P-glycoprotein, whereas 5-OHP is a possible substrate.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1997

Patient-based research in a tertiary pediatric centre: a pilot study of markers of scientific activity and productivity.

OBJECTIVE: To characterize patient-based research in a large academic pediatric centre, to examine measures of research activity and productivity among the 44 clinical programs and to examine whether there is a relation among various measures of scientific productivity. DESIGN: Survey. PARTICIPANTS: Clinical programs. OUTCOME MEASURES: Analysis of all patient-based research projects for the 1993-94 and 1994-95 fiscal years, research funding and cumulative citation impact. RESULTS: Only half of the research projects were funded by extramural grants (peer-reviewed or industrial). There were strong and significant correlations among the 3 markers of scientific activity and productivity: funding, peer-reviewed publications and cumulative citation impact. Only small programs with 3 or fewer faculty members with protected time available to develop research programs achieved a citation impact of 30 or more per full-time equivalent position, with larger programs being "diluted" by clinicians performing little or no research. CONCLUSIONS: In the context of patient-based research, quantity of research correlated with measures of quality. This study highlights the need for clinical departments and medical faculties to consider activity and productivity markers in setting standards for patient-based research.

Hospitals, Pediatric↗
PubMed1997

Review of a home-based palliative care program for children with malignant and non-malignant diseases.

This retrospective chart review presents the patient characteristics and utilization of the home-based palliative care program at The Hospital for Sick Children in Toronto. A total of 126 children dying from a broad spectrum of diseases was admitted during the period 1986-1994, referred from neurosurgery, genetic/metabolic, neurology, neonatology, nephrology, cardiology, general pediatrics, general surgery, and pulmonology. At the time of review, 15 patients remained alive and 18 had been discharged from the program. Mean age at the time of referral was 4.8 +/- 0.51 years and mean age at death was 5.3 +/- 0.55 years. The mean number of days in hospital was 26.5 +/- 14.6 while days spent at home averaged 98.4 +/- 15.2; thus 80% of the children's remaining time was spent at home. The average number of parent-team contacts was 3.5 +/- 0.9 by pager and 24.0 +/- 2.9 by telephone. Of the 93 patients who died in the program, 53% died at home, 18% died in community hospitals, and 29% died in a tertiary care facility. Analgesic medications were administered to 54% of the patients; 56% of these then required opioid analgesia for pain and symptom management. Home-based palliative care appeared to be an effective program for many children with a variety of terminal illnesses after adequate supports for the child and family had been established.

Adolescent↗
PubMed1996

Mild maternal drinking and pregnancy outcome: perceived versus true risks.

Millions of fetuses worldwide every year are exposed to mild maternal alcohol consumption during the first trimester of pregnancy. Health professionals and agencies often suggest that even mild drinking can affect the fetus, despite many studies refuting this fact. To characterize women's perception of the teratogenic risk of alcohol we studied 30 nonpregnant adult women aged 19-52 years. They first watched a videotape which includes alarming information of fetal risk after mild drinking. Following the movie, women's views changed significantly towards believing that even one drink during pregnancy can harm the fetus. Scientists and physicians should refrain from unfounded statement of fetal risks from mild alcohol consumption. These may lead to unnecessary termination of otherwise wanted pregnancies.

Adult↗