Spectroscopic studies of the interactions of the pyrethroid insecticide fenvalerate with gramicidin

Fenvalerate is a pyrethroid insecticide which interacts with ionic channels. Using circular dichroism technique we have studied the interaction of fenvalerate with gramicidin, a model channel peptide which transports ions. In most organic solvents, gramicidin exists as a double helix except in trifluoroethanol where it exists as a channel forming single stranded beta6.3 helical monomer. In model lipid membranes, under certain experimental conditions, gramicidin exists as a channel forming single stranded beta6.3 helical dimer. Our results show that fenvalerate interacts more with the single stranded beta6.3 helical monomer or dimer than with the double helical form of gramicidin. This was further confirmed by an increase in the rate of gramicidin mediated proton transport in liposomes by fenvalerate, using the pH sensitive fluorophore, pyranine.     

Health state preferences of persons with anxiety

We have described a program that integrates clinical approaches of infant mental health to infants and toddlers in foster care. The juxtaposition of a mental health program in a forensic setting creates a number of special features that we have highlighted. Unique from the clinical perspective, the team is explicitly relationship-focused, attempting to understand all of the young child's caregiving relationships as they affect development. We strive to enhance the quality of all of relationships in which infants participate, fostering healthy attachments and development. Also unique is the emphasis on system liaison, and making programmatic efforts to affect various systems involved in making custody determinations about infants and toddlers. Unique from the forensic perspective, we offer multidisciplinary expertise about an especially high-risk population, a comprehensive service delivery system in which we provide or coordinate and monitor all intervention efforts for a given family, a prevention orientation, and clinical follow-up with infants for as long as they are in care. The goals of the program include expediting permanency planning decisions, increasing continuity in high-quality foster care placements, increasing court satisfaction with mental health consultation, decreasing the number of court-ordered evaluations for adjudicated families, and increasing CPS satisfaction with available treatment and continuity of care. We believe that this approach integrates delivery of services to the youngest and most vulnerable victims of maltreatment and expedites permanency planning.     

The selective norepinephrine reuptake inhibitor, LY368975, reduces food consumption in animal models of feeding

PURPOSE: The present study evaluated the cytostatic and apoptotic effects of a 24-hr paclitaxel treatment in ovarian tumors. METHODS: Three-dimensional histocultures of surgical specimens from patients (n = 17) were used. The cytostatic effect was measured by inhibition of 96-hr cumulative DNA precursor incorporation and induction of apoptosis was determined by morphological changes. RESULTS: Paclitaxel produced partial inhibition of DNA precursor incorporation in about 40% of tumors (maximum inhibition of approximately 30%) and induced apoptosis in about 90% of tumors (maximum apoptotic index of approximately 15%). In responsive tumors, maximum cytostatic and apoptotic effects were achieved at < or = 1 microM with no further enhancement by increasing the drug concentration to 10 microM. In individual tumors, the apoptotic effect inversely correlated with cytostatic effect (r2 = 0.27, p = 0.031), and the maximal apoptotic index correlated with the LI for the untreated controls (r2 = 0.38, p < 0.01). More than 95% of apoptotic cells after paclitaxel treatment were labeled with DNA precursor. The incomplete cytostatic and apoptotic effects of paclitaxel and the link between DNA synthesis and apoptosis in ovarian tumors are similar to our previous findings in other human solid tumors. CONCLUSIONS: These findings suggest that (a) apoptosis is the major paclitaxel effect in advanced ovarian tumors, (b) tumor sensitivity to drug-induced cytostatic effect is opposite to sensitivity to apoptotic effect, (c) paclitaxel-induced apoptosis increases with increased cell proliferation and is completed after DNA synthesis, and (d) further increasing the dose to elevate plasma concentration beyond 1 microM may not improve treatment outcome.     

In vitro release of acyclovir from semisolid dosage forms: effect of cyclodextrin and polyethylene glycol

Presynaptic depolarization of trigemino-thalamic (TGT) terminals may contribute to modulation of ascending oro-facial somatosensory information during active (or rapid eye movement) sleep. The relative excitability of TGT terminals was inferred from changes in the current required to maintain an antidromic firing probability of 50% (EC50) during quiet wakefulness as compared to active sleep. Depolarization or hyperpolarization of TGT terminals was defined as a decrease or increase, respectively, in the EC50. Overall, the EC50 of 8 TGT terminals was reduced by a mean 8.8+/-3.6 microA during active sleep relative to quiet wakefulness. This result suggests that depolarization of TGT terminals, which may act to suppress the transfer of sensory information from the trigeminal nucleus to the thalamus, occurs during active sleep.     

Application of a nested, multiplex PCR to psittacosis outbreaks

We developed a nested, multiplex PCR for simultaneous detection of three species of chlamydiae in human and avian specimens. The PCR was designed to increase sensitivity and to circumvent inhibitors of PCR present in clinical specimens. The target sequence was the 16S rRNA gene. The first-step PCR was genus specific, and the second-step PCR was multiplexed (i.e., had multiple primer sets in the same tube) and could discriminate among Chlamydia pneumoniae, Chlamydia psittaci, and Chlamydia trachomatis on the basis of the molecular weight of the amplicon. The limit of detection of each of the two PCR steps was 5 inclusion-forming units. We used PCR and serologic evidence during outbreaks of psittacosis to infer that C. psittaci had been transmitted from birds purchased in pet stores to humans. We also used this method to test both live and dead birds from pet stores for infection with C. psittaci. Compared with culture, the application of PCR to avian specimens increased the rate of C. psittaci detection.     

Head circumference of rural Nigerian children--the effect of malnutrition on brain growth

OBJECTIVE: To compare head circumference measurements of the well nourished with those of the malnourished children for each sex. DESIGN: Cross sectional. SETTING: Imesi, Ile-Ife village, Nigeria. SUBJECTS: 644 children in the first six years of life. MAIN OUTCOME MEASURES: Head circumference. RESULTS: The mean head circumference values of malnourished children of both sexes fell mostly below the values for their well nourished age mates. The curve for well nourished girls fell by a little below, and for malnourished girls by over two standard deviations below Tanner's 50th percentile curve. For the boys, the curve for the malnourished children fell by over one standard deviation below the curve for their well nourished age mates. CONCLUSION: The significant reductions in head circumferences found in malnourished children may have serious implications for their future performance and achievement. Therefore, sufficient community concern and appropriate world action aimed at eradicating protein energy malnutrition is solicited.