Cocaine treatment in neonatal rats affects the adult behavioral response to amphetamine.

This study investigated whether exposure to cocaine during critical periods of brain development alters the motor stimulating effects of amphetamine given in adulthood. Female rats received 50 mg/kg/day cocaine HCl SC or vehicle during either postnatal days 1-10 or 11-20. At 60-65 days of age, activity counts were collected over a 15-min baseline period. Subjects then received one of 3 doses (0, 0.1, 0.25 mg/kg) of d-amphetamine sulfate SC followed by a 90-min period of activity monitoring. Adult activity in 1-10-day cocaine-treated rats was different from vehicle-treated rats in response to 0.1 mg/kg amphetamine only. Adult activity in 11-20-day cocaine-treated rats was different from vehicle-treated rats in response to 0.25 mg/kg only. The observed differences represented an increase and decrease in activity, respectively. These alterations in amphetamine response may be related to the observed alterations in D-1 receptor concentrations as well as the altered rates of brain glucose metabolism we have observed in adult rats neonatally exposed to cocaine.

Speed of color naming and degree of familial sinistrality: correlation in girls, no correlation in boys.

Twenty-nine male and 35 female right-handed children, aged 5 to 7, were assessed for the effect of familial sinistrality on a rapid color-naming task. Controlling for age and family size, a significant effect for degree of familial sinistrality was found in the girls but not in the boys. Among the girls, those with two or more left-handed or ambidextral relatives were the fastest on the color-naming task, those with no such relatives were the slowest, and those with only one left-handed or ambidextral relative scored between the other two groups in color-naming speed. It is suggested that a gene associated with left-handedness, when present in a right-hander, interacts with sex to produce the superior color-naming performance that we observed in girls but not in boys.

Speed of color naming and intelligence: association in girls, dissociation in boys.

We administered a rapid naming test to a sample of prereaders. Slow performance on this task among older children is known to be associated with reading disability. Results showed a sex difference in the degree of correlation between naming performance and a test of general intelligence. The finding was replicated on an independent sample. This finding bears theoretically on the degree to which a learning disability can appear as an isolated deficit in the two sexes.

Vaginal colonization with Group B beta-hemolytic streptococcus as a risk factor for post-cesarean section febrile morbidity.

Vaginal colonization of mothers with Group B beta-hemolytic streptococcus (GBS) has been recognized as a risk factor for neonatal morbidity. The relationship of GBS colonization to risks for the mother who undergoes cesarean section has not been defined. In this study, we found that, among patients who underwent cesarean section, the 19% of them who were colonized with GBS had a higher incidence of standard fever (66.6% vs. 30.5%), clinical diagnosis of endomyometritis (61.1% vs. 12.5%), and use of antibiotics (61.1% vs. 26.3%) in relationship to a significantly increased frequency of premature rupture of the membranes (50.0% vs. 14.8%). Reasons for the association between vaginal colonization and increased morbidity are discussed.

Source of Pseudomonas in osteomyelitis of heels.

Pseudomonas aeruginosa is the most common cause of osteomyelitis following puncture wounds of the feet of children. The source of the initial inoculum is unknown. Only one strain of P. aeruginosa was cultured from paired samples of the heel or corresponding shoe's surface or both obtained from 100 children. Neither the skin of the heel nor the shoe appears to be the source of the initial inoculum.

Listeria monocytogenes: brain abscess or meningoencephalitis?

A brain abscess caused by Listeria monocytogenes developed in an immunosuppressed renal transplant patient. Meningitis and meningoencephalitis from this organism were encountered in three other renal transplant recipients at this medical center during the past 4 years. Focal neurologic deficits occurred in patients with either Listeria abscess or meningoencephalitis. Computerized tomography was a rapid aid to the diagnosis of abscess. Immunosuppression has increased the incidence of central nervous system Listeria infections, but ampicillin still provides effective treatment, even when immunosuppressive therapy is continued. Limited experience with Listeria brain abscess suggests that surgical intervention improves the prognosis.