Perceptual learning: insight in sight.

The Hebbian synapse and Hebb learning rule are familiar to those working on biological and machine learning. But Hebb's insights from over fifty years ago carry many other lessons in learning and may contribute to a more parsimonious taxonomy of the mechanisms involved.

Staphylococcal accessory regulator (sar) in conjunction with agr contributes to Staphylococcus aureus virulence in endophthalmitis.

Previous studies showed that an agr mutant strain of Staphylococcus aureus was partially attenuated in virulence compared to a parental strain in experimental endophthalmitis. The purpose of this study was to determine whether the sar locus, either alone or through interactions with agr, contributes to the regulation of virulence in S. aureus endophthalmitis.

Host/parasite interactions in bacterial endophthalmitis.

Bacterial infections within the eye arise as complications of intraocular surgery, penetrating injury, or hematogenous spread from distant anatomical sites. Because: 1) the interior surfaces of the eye are lined with sensitive, nonregenerating tissues, 2) the inner chambers of the eye are relatively sequestered from circulating immunological components, 3) the integrity of blood-ocular barriers provides poor penetration of systemically administered antibiotics, and 4) aqueous and vitreous humor represent rich, relatively acellular culture media; endophthalmitis often progresses rapidly and total loss of vision frequently results. Years of clinical experience have shown that current therapies for endophthalmitis, including antimicrobials, antiinflammatory agents, and vitrectomy, are frequently unsuccessful in ameliorating destruction of intraocular tissues.

Health-promoting schools in Australia: models and measurement.

Schools represent a very attractive setting for health promotion. Most children and young people attend school, professional educators are in place, and most school communities are microcosms of the larger community, providing opportunities for children to develop and practice the skills necessary to support a healthy life-style. In response to this opportunity, the precepts of contemporary health promotion have been synthesised into the 'health-promoting school' model, which is guided by a holistic view of health and by the principles of equity and empowerment.

Physical activity preferences, preferred sources of assistance, and perceived barriers to increased activity among physically inactive Australians.

Background: Participation in regular moderate or vigorous physical activity substantially reduces risk for all-cause and cardiovascular-disease mortality and confers other health benefits. Efforts to decrease the population prevalence of inactivity will have a greater impact if they are tailored to the needs and preferences of the community.

Methods: In the Pilot Survey of the Fitness of Australians, a questionnaire was administered to a randomly selected sample of 2,298 adults and included questions on the preferred sources of assistance or support to become physically active, preferred activities, and barriers to regular participation.

Molecular epidemiology and significance of a cluster of cases of CMV infection occurring on a special care baby unit.

Sequencing of the amino-terminal region of the glycoprotein H gene was used to investigate the possibility of a common source for cytomegalovirus (CMV) infection occurring in five premature babies. All but two of the strains were different, indicating that this cluster of infection occurring on the special care baby unit was unlikely to be epidemiologically linked.

The morbidity attributable to Schistosoma japonicum infection in 3 villages in Dongting Lake region, Hunan province, PR China.

In common with other helminth infections, symptoms associated with Schistosoma japonicum infection have a low specificity, and many infections are asymptomatic. The presence of the parasite in a sick individual from an endemic area does not mean that S. japonicum is the aetiological agent.

Structural analysis and proteolytic activation of Enterococcus faecalis cytolysin, a novel lantibiotic.

Clinical isolates of Enterococcus faecalis more commonly produce a cytolysin than do commensal isolates. Epidemiologic evidence and animal-model studies have established a role for the cytolysin in the pathogenesis of enterococcal disease. The cytolysin consists of two structural subunits, CylLL and CylLS, that are activated by a third component, CylA.

Clinical aspects of nurse anesthesia practice. Sedation and monitored anesthesia care.

Safe monitoring of patients receiving sedation mandates that all care givers recognize the potential physiologic trespass of sedatives, hypnotics, and opioid-like drugs on cerebral or respiratory systems. They must be ready to recognize this affront immediately, have necessary resuscitative equipment available, possess prerequisite skills to intervene in adverse changes, and know when to seek additional help. The long history of CRNA practice has helped to define nursing roles in this important form of perioperative care.

Helminth infections, morbidity indicators and schistosomiasis treatment history in three villages, Dongting Lake region, PR China.

In order to estimate the public health impact of helminth infections, and to provide baseline data for interventions, parasitological and morbidity surveys were conducted among inhabitants of three villages in Dongting Lake region, Hunan Province, China. Ascaris lumbricoides was found to be the most common helminth infection, followed by Trichuris trichiura and Schistosoma japonicum. Left liver enlargement was the most common indicator of morbidity.

Altered cognitive functioning in children with idiopathic epilepsy receiving valproate monotherapy.

Once a child is diagnosed with epilepsy, a primary concern is whether or not the child's behavior and cognitive abilities will be affected by the disease, by the drug prescribed for seizure control, or both. Direct cognitive effects by the epileptic condition have been described. On the other hand, cognitive effects in epilepsy have been attributed to antiepileptic drug therapy.

Relationship between a 14-day recall measure of leisure-time physical activity and a submaximal test of physical work capacity in a population sample of Australian adults.

This paper reports on the validity of a 14-day recall measure of leisure time physical activity (LTPA) in a sample of Australian adults (N = 986). Submaximal cycle ergometry was used to assess physical work capacity per kilogram of body mass (pwc75/kg). The self-report energy expenditure estimates were used to categorize respondents as vigorously active, moderately active, and low active/sedentary.

recA-dependence of the response of Pseudomonas aeruginosa to UVA and UVB irradiation.

The responses of the autochthonous soil and aquatic organism, Pseudomonas aeruginosa to UV radiation wavelengths (UVA, 320-400 nm, and UVB, 280-320 nm) has been investigated in this study. P. aeruginosa recA mutants were found to be more sensitive to both UVA and UVB radiation than were their isogenic RecA+ parents.

Development of public policy and physical activity initiatives internationally.

Epidemiological, pathological, clinical, and experimental studies over the past 40 years convincingly show that physical inactivity and low physical fitness contribute substantially to the major chronic diseases prevalent in industrialised societies. Several industrialised countries around the world report increases in physical activity participation among adults in recent years, but the prevalence of inactivity remains high. These increases in voluntary exercise are at least partially offset by decreasing daily energy demands due to increased mechanisation at home, at work and during leisure-time.

Retest reliability of recall measures of leisure-time physical activity in Australian adults.

Background: Several studies have reported that short-term recall measures of physical activity participation have acceptable repeatability, but in most cases employed convenience samples and did not use optimal statistics. In this Australian study repeatability was assessed on participants recall of activity over two different time periods and over the same time period.

Methods: Two 14-day recall measures of physical activity participation were administered in two studies to randomly selected population samples of adults in Adelaide, South Australia.

Single-Strand Conformation Polymorphism Mutation Analysis of the p53 Gene.

Single-strand conformation polymorphism (SSCP) is a rapid and convenient procedure by which differences in the base composition of short DNA strands may be detected (1, 2). A useful application of this is in the comparison of polymerase chain reaction (PCR) generated products from gene coding sequences of unknown or patient material with a known wild-type standard; where any deviation of the banding pattern produced by the former from that produced by the latter indicates a possible mutation within the sequence of that product.

Asthma, health behaviors, social adjustment, and psychosomatic symptoms in adolescence.

The association of health behaviour, indicators of social adjustment, and psychosomatic symptoms with diagnosed asthma was assessed in a community-based sample of 4550 adolescents in South Western Sydney, Australia. The results of this survey found an asthma prevalence among 11-15-year-olds of 17.5%, being consistent with previous studies.

Estimating the number of multiple-species geohelminth infections in human communities.

Infections with Ascaris lumbricoides, Trichuris trichiura and the hookworm species are often found in the same communities and individuals. Hosts infected by more than one species are potentially at risk of morbidity associated with each infection. This paper describes the use of a probabilistic model to predict the prevalence of multiple-species infections in communities for which only overall prevalence data exist.

Hepatic cryotherapy for metastatic liver tumours.

Liver resection is the treatment of choice for resectable hepatic metastases; however, most patients have unresectable disease when diagnosed. Hepatic cryotherapy has been advocated to treat unresectable tumours in the liver although its precise role is still being evaluated. This article discusses mechanisms of action, technical considerations, current indications and the early results of cryotherapy in treating metastatic liver disease.

The development of an age structured model for schistosomiasis transmission dynamics and control and its validation for Schistosoma mansoni.

Mathematical models are potentially useful tools to aid in the design of control programmes for parasitic diseases. In this paper, a fully age structured epidemiological model of human schistosomiasis is developed and parameterized, and used to predict trends in infection prevalence, intensity and prevalence of heavy infections over age and time during several rounds of mass and age targeted treatment. The model is validated against data from a Schistosoma mansoni control programme in Kenya.

BCL-2 expression by leukaemic blasts in a SCID mouse model of biphenotypic leukaemia associated with the t(4;11)(q21;q23) translocation.

Acute leukaemia of infancy is associated with abnormalities at chromosome band 11q23, and has a poor prognosis. The gene involved. Mixed Lineage Leukaemia (MLL), has been identified and has the characteristics of a transcription factor.