Tactile stimulation and maternal separation prevent hippocampal damage in rats submitted to neonatal hypoxia-ischemia

Unilateral neonatal hypoxia-ischemia causes important damage to the hippocampus of the hemisphere ipsilateral to carotid artery occlusion; two forms of neonatal handling, tactile stimulation and maternal separation for a short period, have been shown to produce functional/behavioral protection in distinct models of CNS challenge. In this paper we investigated whether neonatal handling could alter the hippocampal damage caused by neonatal hypoxia-ischemia (HI) in the Wistar rat. Pups at postnatal day 7, P7, received HI (8% O(2)-92% N(2)) for 90 min and were submitted to neonatal handling, tactile stimulation of maternal separation daily, from P8 to P21, for 10 min. On adulthood, hippocampal volume was analyzed by stereological techniques, along with measures of cortical thickness and hemispheric area at the level -3.30 mm from bregma. HI caused a reduction of volume of whole hippocampus, of Amon's horn and of dentate gyrus, with no effect on cortical and hemispheric measures; neonatal handling prevented such effect. This is the first report showing that both tactile stimulation and neonatal handling exert a morphological neuroprotective action for HI-induced damage to the hippocampus.     

The metabolism and binding of ( 14 C)mycophenolic acid in the rat

Seventeen h after the intraperitoneal administration of 33 mg/kg of [¹⁴C]mycophenolic acid to rats, radioactivity was bound to the tissues of the intestines, bladder, stomach, kidney, liver and lung in decreasing order; no binding to spleen tissue was observed. In vitro incubations of the agent with macromolecules resulted in the binding of radioactivity to salmon sperm DNA and to bovine plasma albumin, the extent of binding being increased and decreased, respectively, in the presence of a rat liver microsomal system. The binding was apparently covalent since repeated purification procedures failed to release the bound radioactivity; heating of [¹⁴C]mycophenolic acid bound-DNA in n hydrochloric acid at 100° for 2 h caused the release of the bound radioactivity. Under the conditions described, 43% of the administered radioactivity was excreted in the urine (33%) and faeces (10%); the urine contained free mycophenolic acid (13%), mycophenolic acid glucosiduronate (17%) and an uncharacterized metabolite (3%).     

Phenytoin withdrawal and seizure frequency

We withdrew phenytoin from 17 inpatients maintained on combination therapy with carbamazepine for complex partial seizures and analyzed seizure occurrence in relation to plasma levels and time from initiation of withdrawal. The ratio of maximum to mean weekly seizure frequency did not vary with initial level or rate of withdrawal. The week with most frequent seizures began a median of 10 days after phenytoin levels became undetectable, and mean daily seizure frequency was higher at undetectable than at falling levels for the entire 2- to 10-week study period. Four patients had a total of 6 clusters of generalized tonic-clonic seizures; only 2 occurred while levels were falling and the other 4 at 3, 9, 28, and 42 days after reaching undetectable levels. Our data argue against the occurrence of withdrawal seizures in these patients and suggest that worsening of seizures following phenytoin discontinuation more likely reflects loss of therapeutic drug effect than a true abstinence phenomenon.     

Barium impaction as a cause of small bowel obstruction in an infant with cystic fibrosis

Small bowel obstruction in children with cystic fibrosis due to the impaction of barium is an unusual occurrence. This is the report of an 8.5-month-old black male who had an upper GI series on the day of discharge from the hospital, and returned the next day with a distal small bowel obstruction due to a barium impaction.     

High-performance liquid chromatographic analysis of the tyrphostin AG1478, a specific inhibitor of the epidermal growth factor receptor tyrosine kinase, in mouse plasma

The tyrphostin 4-(3-chloroanilino)-6,7-dimethoxyquinazoline (AG1478) is undergoing evaluation as a potential new anticancer agent. We have developed a specific and sensitive reversed-phase HPLC assay for AG1478 in mouse plasma. The method involves a rapid and simple extraction process followed by separation on a Symmetry C8 stationary phase with a gradient of acetonitrile in ammonium acetate buffer. A linear response was achieved over the concentration range of 0.2-100 microM using multilevel calibration with internal standard method of calculation. Inter- and intra-assay accuracy and precision were better than +/-10%. The limit of quantitation was 0.2 microM. We have used this method to study the preclinical pharmacokinetics of this new agent in mice.     

Can family-centered programing mitigate HIV risk factors among orphaned and vulnerable adolescents? Results from a pilot study in South Africa

Let's Talk is a structured, family-centered adolescent HIV prevention program developed for use in South Africa using key components adapted from programs successfully implemented in the US and South Africa. It is designed to address individual HIV transmission risk factors common among orphaned and vulnerable adolescents, including elevated risk for poor psychological health and sexual risk behavior. These efforts are accentuated through parallel programing to support caregivers’ mental health and parenting skills. Twelve Let's Talk groups, each serving approximately 10 families, were piloted by two local community-based organizations in Gauteng and Kwa-Zulu Natal provinces, South Africa. Face-to-face interviews were conducted among participating caregivers and adolescents at baseline and three months post-intervention to explore the potential effects of the program on intermediate outcomes that may support HIV preventive behavior. Specifically, generalized estimation equations were used to estimate average change on HIV prevention knowledge and self-efficacy, caregiver and adolescent mental health, and family dynamics. Among the 105 adolescents and their 95 caregivers who participated in Let's Talk and completed both surveys, statistically significant improvements were found for adolescents’ HIV and condom use knowledge as well as condom negotiation self-efficacy, but not sexual refusal self-efficacy. Both caregivers and adolescents demonstrated significantly better mental health at post-test. Adolescent/caregiver connection and communication about healthy sexuality also improved. These preliminary results highlight the potential of HIV prevention interventions that engage caregivers alongside the vulnerable adolescents in their care to mitigate adolescent HIV risk factors. A more rigorous evaluation is warranted to substantiate these effects and identify their impact on adolescents’ risk behavior and HIV incidence.     

The results of high-frequency duplex surveillance after iliac arterial stenting in a single center

Frequent duplex surveillance after iliac arterial stenting is time-consuming and costly, so solid benefits of this approach must be available. Frequent duplex surveillance was performed at our center, this was reviewed retrospectively.A total of 117 stents were assessed. Duplex was done for 84 (71.8%) of 117 patients at 1 year and 25 (21.4%) of 117 at 5 years, mean follow-up 27.6 months. Totally, 456 scans were performed; 386 (84.6%) scans were normal, 43 (9.4%) showed an abnormality for which intervention was not necessary, 27 (5.9%) showed abnormalities which needed interventions. The maximum attendance of patients was 62%. In all, 18 patients had interventions unrelated to scheduled follow-up; 15 (83.3%) of 18 had no prior abnormalities on duplex, 3 (16.6%) of 18 had prior abnormalities which were not acted upon after clinical assessment. Our findings demonstrate a high nonattendance rate with frequent emergency presentations due to acute complications. We cannot, therefore, recommend frequent duplex surveillance program both in terms of results or resource allocation.