Environmental drivers of parasite load and species richness in introduced parakeets in an urban landscape.

Introduced species represent a threat to native wildlife worldwide, due to predation, competition, and disease transmission. Concurrent introduction of parasites may also add a new dimension of competition, i.e. parasite-mediated competition, through spillover and spillback dynamics. Urban areas are major hotspots of introduced species, but little is known about the effects of urban habitat structure on the parasite load and diversity of introduced species. Here, we investigated such environmental effects on the ectoparasite load, richness, and occurrence of spillback in two widespread invasive parakeets, Psittacula krameri and Myiopsitta monachus, in the metropolitan area of Rome, central Italy. We tested 231 parakeets and found that in both species parasite load was positively influenced by host abundance at local scale, while environmental features such as the amount of natural or urban habitats, as well as richness of native birds, influenced parasite occurrence, load, and richness differently in the two host species. Therefore, we highlight the importance of host population density and habitat composition in shaping the role of introduced parakeets in the spread of both native and introduced parasites, recommending the monitoring of urban populations of birds and their parasites to assess and manage the potential occurrence of parasite-mediated competition dynamics as well as potential spread of vector-borne diseases.

Construction of an inducible system for the analysis of essential genes in Yersinia pestis.

Yersinia pestis, a Gram negative bacterium, causes bubonic and pneumonic plague. Emerging antibiotic resistance in clinical isolates is driving a need to develop novel antibiotics to treat infection by this transmissible and highly virulent pathogen. Proteins required for viability, so called essential genes, are attractive potential therapeutic targets, however, confirmation of essentiality is problematic. For the first time, we report the development of a system that allows the rapid determination of Y. pestis gene essentiality through mutagenesis and inducible expression of a plasmid borne copy of the target gene. Using this approach, we have confirmed the uridine monophosphate kinase PyrH as an essential protein in Y. pestis. This methodology and the tools we have developed will allow the confirmation of other putative essential genes in this dangerous pathogen, and facilitate the identification of novel targets for antimicrobial development.

Changing referral patterns to a designated craniofacial centre over a four-year period.

Craniofacial conditions are mainly treated within England by four supra-regional centres. Due to a continuous increase in the number of cases referred to our service we audited the source and nature of these referrals. Data was prospectively collected over a four-year period from April 2004 to March 2008. The speciality of the referring clinicians was recorded, along with the diagnosis. A year-by-year increase in the number of referrals from 138 in 2004-2005 to 253 in 2007-2008 was seen. There was a 214% increase in the number of patients referred with single suture craniosynostosis, a 520% increase in patients with benign hyperplastic conditions such as fibrous dysplasia, neurofibromatosis and vascular anomalies and a 220% increase in patients treated elsewhere but now needing revision surgery. A 407% increase in referrals for positional plagiocephaly was recorded. Our referral pattern reflects the internationally accepted increase in the incidence of metopic synostosis and positional plagiocephaly. Due to the skill mix and experience present in a designated craniofacial service other benign hyperplastic and hypoplastic conditions are increasingly being referred. Additional referrals have come from a change in the referral pathway. To manage the increased workload we have established separate clinics to manage vascular anomalies and have adopted a policy of not reviewing patients with positional plagiocephaly.

Better care and better teaching. New model of postpartum care for early discharge programs.

PROBLEM BEING ADDRESSED: Rapid postpartum discharge has reduced opportunities to detect early newborn or parenting problems and to teach neonatal assessment and maternal postpartum care to medical trainees. OBJECTIVE OF PROGRAM: Development of a program to not only ensure adequate care of mothers and newborns after early hospital discharge, but also to teach outpatient assessment skills to family medicine residents. MAIN COMPONENTS OF PROGRAM: In an urban, secondary care, university-affiliated teaching hospital predominantly training family medicine residents, an interdisciplinary committee created and supervised a neonatal and maternal postpartum assessment program. Newborn infants and their mothers are seen by a family physician, a family medicine resident, and a nurse within 48 hours of discharge, after which care is assumed in the community by the child's primary care physician. An assessment protocol developed by the interdisciplinary group promotes standardized mother and child care and a structured learning experience for trainees. CONCLUSION: Rapid follow up of early discharged infants and their mothers can be facilitated by a program of standardized assessment by a roster of pooled, interacting family physicians and nurses. When this assessment occurs in a teaching milieu, a comprehensive learning experience can be combined with defined objectives that emphasize and encourage newborn and maternal assessment for ambulatory patients.

Porcelain for veneers.

An ideal porcelain veneer placed on a non-discolored tooth requires the least amount of tooth preparation and the use of a translucent porcelain that interferes minimally with the transmission of light. In contrast, veneering a discolored tooth requires additional tooth preparation and the use of a chromatic or opacious porcelain. This article discusses several criteria for the selection of porcelain for porcelain veneers, including some steps to enhance the esthetic properties of these restorations.

Direct inhibitory effect of atriopeptin III on renin release in primate kidney.

Patterns of in vitro renal renin release and the ability of atriopeptin to directly inhibit renin release have been examined in the rat, rabbit, and dog, but have been unstudied in the primate kidney. Accordingly, we examined renin release from superficial renal cortical slices of the squirrel monkey (Samiri sciuresus). The average age of the 5 animals was 10.2 +/- 2.5 yr at the time of study. Renin release was stimulated significantly by the beta-adrenergic agonist isoproterenol in concentrations of 10(-5) M (1.67-fold) and 10(-4) M (1.84-fold). Isoproterenol-induced renin release was inhibited by atriopeptin III (ANP, 2 X 10(-8) M) and the adenylate cyclase inhibitor dideoxadenosine (DDA, 10(-5) M). Similarly, the incubation of the superficial cortical slices with arachidonic acid (10(-3) M) resulted in a 4-fold increase in tissue renin release which was blocked by the calcium ionophore A23187 (17 X 10(-6) M) and ANP; interestingly, DDA did not block arachidonic acid-induced renin release. These results suggest that ANP exerts a direct inhibitory effect on B-adrenergic and arachidonic acid-induced renin release in the primate kidney. Further, the inhibitory action of A23187 on renin release suggests, as in other species, an integral role for intracellular calcium in the renin release process. These patterns of renin release in primate kidney are similar to those observed in the rodent kidney in vitro.

A radiometric system for airborne measurement of the total heat flow from the sea.

An airborne system for measurement of the total heat flow from the sea has been developed and used successfully during the BOMEX exercises in May 1969. Details of the system are described, and its operation is illustrated by one day's results at Barbados, W. I. Continuous recalibration of detector sensitivity was a major improvement which permits measurement of sea surface temperature to 0.01 degrees C.