Endothelin-1 inhibits basal and human chorionic gonadotrophin-stimulated progesterone production

Endothelin-1 (ET-1) is a peptide classically produced by endothelial cells and known for its powerful vasoconstrictor activity. However, recent data suggest an involvement of ET-1 also in reproductive function. This study was designed to examine the possible presence and role of ET-1 in human luteal cells. Purified luteal cells were incubated for different times with ET-1 (10(-9)-10(-6) M) or ET-3 (10(-9)-10(-6)) alone or associated with human chorionic gonadotrophin (HCG) (100 ng/ml). Both basal and HCG-induced progesterone production were significantly reduced by ET-1 at all examined times whereas preincubation of luteal cells with BQ485 (10(-9)-10(-6) M), an ET-A receptor antagonist, prevented the inhibitory effect of ET-1. Conversely, no effect on progesterone synthesis was observed when ET-3 was added to the cultures. Luteal cells were then incubated for 24 h with phorbol 12-myristate-13 acetate (PMA) (100 ng/ml), an activator of protein kinase C. Inhibition of progesterone synthesis by PMA was similar to that induced by ET-1 alone. This study demonstrates that ET-1 negatively affects, at physiological concentrations, basal and HCG-induced progesterone synthesis. These effects seem to be exerted through the ET-A receptors and the protein kinase C pathway. Conversely, ET-3 was not able to influence human luteal steroidogenesis.     

Repetition priming and experimental context effects

Solving belief problems develops as a skill in normal children during the preschool years. To understand this process of development, it is necessary to provide an analysis of the tasks used to test preschool 'theory of mind' skills. This analysis should allow us to relate the structure of a given task to the underlying cognitive mechanisms that the task engages. In two experiments, we find that 3-year-old children show a pattern of success and failure on belief tasks that is not consistent with 'conceptual deficit' accounts. Young children possess the concept, BELIEF, but have certain characteristic difficulties with correctly calculating the contents of beliefs. In childhood autism, by contrast, the mechanisms that in normal development bestow conceptual competence in this domain are impaired. In the first experiment, parallel task structures are used to show that 3-year-olds are no better at predicting behavior from a partially true belief than they are at predicting behavior from an entirely false belief. We develop specific proposals about task structural factors that either facilitate or hinder success in belief-content calculation. These proposals are supported in a second experiment. We compare two false-belief tasks, one of which has helpful structural factors, the other of which has hampering factors, with a third task which exemplifies a hampering task structure but without any theory of mind content. We compare 3- and 4-year-olds' patterns of performance with that of autistic children. Each of the three groups shows a distinct performance profile across the three tasks, as predicted for each case by our model. Innate attentional mechanisms provide the conceptual foundations for 'theory of mind' but must be supplemented by a robust executive process that allows false beliefs to achieve 'conceptual pop-out.' Our approach has general implications for the study of conceptual development.     

Interposition grafting for reoperation on the common femoral artery

PURPOSE: This report details our experience with common femoral artery resection and Dacron interposition grafting in the management of vascular reoperations involving the common femoral artery. DESIGN: Retrospective review. SETTING: University teaching hospital. SUBJECTS: Consecutive reoperative patients who had common femoral artery interposition grafting for arteriosclerotic occlusive disease from 1986 to 1997. INTERVENTIONS: Common femoral artery resection and interposition grafting. MAIN OUTCOME MEASURES: Operative morbidity and mortality rates and long-term patency, limb salvage, patient survival, freedom-from-graft-infection, and freedom-from-reoperation rates. RESULTS: Ninety-nine common femoral arteries (16 bilateral) were resected and replaced with Dacron interposition grafts in 83 patients (50 male, 33 female; mean age, 65 years) who had had 237 previous ipsilateral common femoral artery operations (mean, 2.4 operations; range, 1-9 operations). Simultaneous infrainguinal bypass grafts were performed in 52 operations (53%), and 60 operations (61%) were performed in patients who had had previous ipsilateral proximal bypass grafts. Operative mortality was 2%, with a 14% rate of perioperative wound complications. Mean follow-up time was 22 months. One- and 3-year assisted primary patency rates for the interposition grafts were 90% and 77%, respectively. Both 1- and 3-year life-table-determined limb salvage rates were 95%. One- and 3-year life-table-determined freedom-from-reoperation rates were 74% and 43%, respectively. One- and 3-year life-table-determined freedom-from-infection rates were 99% and 92%, respectively. One- and 3-year life-table-determined survival rates were 82% and 73%, respectively. CONCLUSIONS: Common femoral artery resection and Dacron interposition grafting are safe, and they obviate many difficulties associated with reoperative common femoral artery surgery with satisfactory long-term results.     

Widespread unilateral increased rib uptake on bone scan

Some neuropathological changes characteristic of aging and Alzheimer's disease (AD) in humans are present also in senescent non-human primates. The human apoE4 allele is associated with an increased risk of developing late-onset familial and sporadic AD. We found that rhesus monkeys and three subspecies of squirrel monkeys are homozygous for apoE phenotype with arginine at positions 112 and 158 as in human apoE4. However, in both species threonine replaces arginine at position 61 of human apoE. It was previously shown that arginine 61 was critical in determining apoE4 lipoprotein distribution in humans.     

Overestimate of vaccine coverage? New evidence from a survey in Pau da Lima]

To evaluate vaccination coverage in children 0 to 5 years of age, a cross-sectional study based on a household survey was carried out in 1992 in the Pau de Lima Health District, Salvador, Bahia, Brazil, using a cluster sampling technique. The district was subdivided into 30 small areas that were homogeneous with respect to socioeconomic characteristics. Information on the vaccination status of 385 children was obtained through verification of a vaccination card or campaign voucher, or, in the absence of these items, through verbal confirmation from the mother or other responsible person. Based on all the sources of information, the study found vaccination coverage rates in the entire age range of 69% for polio vaccine; 56% for DTP; 74% for measles vaccine; and 87% for BCG. These results suggest that rates obtained from routine records of the health services and vaccination campaigns may be overestimates. The authors discuss the implications of the low coverage rates found in the entire age group and especially among children under 1 year old.     

Water supplementation of infants in the first month of life

OBJECTIVE: To describe the prevalence of and risk factors associated with regular water supplementation of neonates. DESIGN: Evaluation of data from the Food and Drug Administration's Infant Feeding Practices Study, a panel study of US women of fairly high socioeconomic status who were followed up from late pregnancy through their infants' first year of life. The sample was drawn from a nationally distributed consumer mail panel. Each mother was asked whether she gave her neonate water at least 3 times per week. PARTICIPANTS: A total of 1677 mothers of infants who were neonates in April through November 1993. MAIN OUTCOME MEASURES: Percentages of mothers who gave their neonates water at least 3 times a week, considering infant feeding status, mother's education, and family income. RESULTS: About one fourth (24.7%) of the mothers reported giving their neonates water at least 3 times per week. Stratification by feeding practices and socioeconomic factors revealed that 41.6% of mothers who formula-fed their neonates, 47.4% of mothers with less than a high school education, and 35.4% of mothers with an annual family income less than $22,500 gave their neonates water at least 3 times per week. CONCLUSIONS: Water supplementation of neonates was a prevalent practice in this cohort of women. Feeding practices, maternal education, and family income were all significant risk factors associated with this behavior.