Synaptic heterogeneity and stimulus-induced modulation of depression in central synapses.

Short-term plasticity is a pervasive feature of synapses. Synapses exhibit many forms of plasticity operating over a range of time scales. We develop an optimization method that allows rapid characterization of synapses with multiple time scales of facilitation and depression.

Cell surface-expressed Thomsen-Friedenreich antigen in colon cancer is predominantly carried on high molecular weight splice variants of CD44.

Increased mucosal expression of TF, the Thomsen-Friedenreich oncofetal blood group antigen (galactose beta1-3 N-acetylgalactosamine alpha-) occurs in colon cancer and colitis. This allows binding of TF-specific lectins, such as peanut agglutinin (PNA), which is mitogenic to the colorectal epithelium. To identify the cell surface TF-expressing glycoprotein(s), HT29 and Caco2 colon cancer cells were surface-labeled with Na[(125)I] and subjected to PNA-agarose affinity purification and electrophoresis.

Psychoanalysis and cognitive behaviour therapy--rival paradigms or common ground?

The author suggests that contemporary enthusiasm for cognitive-behavioural therapy reflects our longing for swift, rational help for psychological suffering. Competition for funding threatens the psychoanalytic presence in the public sector. The psychoanalytic and cognitive-behavioural models are contrasted, and the relative richness of the psychoanalytic paradigm outlined.

Aggressive incidents in first-episode psychosis.

Background: Recent research has reported increased risk of aggressive incidents by individuals with psychotic illness.

Aims: To examine acts of aggression in first-episode psychosis.

Method: Subjects with a first-episode psychosis were ascertained from a defined catchment area (Nottingham, UK) and reassessed at 3 years (n=166) using clinical interview, informants, health care and forensic records.

Opposite effects on human colon cancer cell proliferation of two dietary Thomsen-Friedenreich antigen-binding lectins.

Increased cell surface expression of the Thomsen-Friedenreich antigen (TF antigen, Galbeta1-3GalNAcalpha-) is a common feature in malignant and pre-malignant epithelia. Our previous studies have shown that dietary TF-binding lectins from peanut (Arachis hypogea) and edible mushroom (Agaricus bisporus) produce marked but different effects on human intestinal epithelial cell proliferation. This study investigates the proliferative effects of the other two known dietary TF-binding lectins: jacalin (Artocarpus integrifolia, JAC) and amaranth lectin (Amaranthus caudatus, ACA).

Neural ensemble coding and statistical periodicity: speculations on the operation of the mind's eye.

Statistical periodicity is a statistical property of densities which arises in the description of retarded dynamical systems. This property is particularly attractive as a possible mechanism for the ensemble coding of information in the nervous system because it operates rapidly and has high storage capacity. For a population of neurons which exhibits statistical periodicity, information would not be encoded by the periodicity, but rather by the spatio-temporal distributions of neural activity.

Psychoanalysis and the moral high ground.

The author reflects on the power and ubiquity of moral issues in the human psyche and thus inevitably in psychoanalysis, and suggests that our moral sense may be an adaptive biological strategy. Goodness is sought in others and aspired to in the self, as part of an innate need to build the ego upon experiences of good objects. Kleinian theory suggests a 'natural morality' that can be discerned in the move towards the 'depressive position', involving increasing care and concern for others.

Structural basis for the resilience of efavirenz (DMP-266) to drug resistance mutations in HIV-1 reverse transcriptase.

Background: Efavirenz is a second-generation non-nucleoside inhibitor of HIV-1 reverse transcriptase (RT) that has recently been approved for use against HIV-1 infection. Compared with first-generation drugs such as nevirapine, efavirenz shows greater resilience to drug resistance mutations within HIV-1 RT. In order to understand the basis for this resilience at the molecular level and to help the design of further-improved anti-AIDS drugs, we have determined crystal structures of efavirenz and nevirapine with wild-type RT and the clinically important K103N mutant.

Multistability in recurrent neural loops arising from delay.

The dynamics of a recurrent inhibitory neural loop composed of a periodically spiking Aplysia motoneuron reciprocally connected to a computer are investigated as a function of the time delay, tau, for propagation around the loop. It is shown that for certain choices of tau, multiple qualitatively different neural spike trains co-exist. A mathematical model is constructed for the dynamics of this pulsed-coupled recurrent loop in which all parameters are readily measured experimentally: the phase resetting curve of the neuron for a given simulated postsynaptic current and tau.

Spontaneous fluctuations in pupil size are not triggered by lens accommodation.

Fluctuations in pupil size and lens accommodation are measured concurrently under open loop conditions, constant illumination and far fixation. In 12/17 trials no correlation was measured between the fluctuations in pupil size and lens accommodation. For the remaining 5/17 trials no lag was observed between the changes in pupil size and lens accommodation indicating that this correlation does not arise as a consequence of a near response.

Identification of genes regulated by UV/salicylic acid.

Purpose: Previous work from the authors' group and others has demonstrated that some of the effects of UV irradiation on gene expression are modulated in response to the addition of salicylic acid to irradiated cells. The presumed effector molecule responsible for this modulation is NF-kappaB. In the experiments described here, differential-display RT-PCR was used to identify those cDNAs that are differentially modulated by UV radiation with and without the addition of salicylic acid.

Phenylethylthiazolylthiourea (PETT) non-nucleoside inhibitors of HIV-1 and HIV-2 reverse transcriptases. Structural and biochemical analyses.

Most non-nucleoside reverse transcriptase (RT) inhibitors are specific for HIV-1 RT and demonstrate minimal inhibition of HIV-2 RT. However, we report that members of the phenylethylthiazolylthiourea (PETT) series of non-nucleoside reverse transcriptase inhibitors showing high potency against HIV-1 RT have varying abilities to inhibit HIV-2 RT. Thus, PETT-1 inhibits HIV-1 RT with an IC(50) of 6 nM but shows only weak inhibition of HIV-2 RT, whereas PETT-2 retains similar potency against HIV-1 RT (IC(50) of 5 nM) and also inhibits HIV-2 RT (IC(50) of 2.

Modulation of retinal pigment epithelial cell behavior by Agaricus bisporus lectin.

Purpose: To determine whether Agaricus bisporus lectin (ABL) binds retinal pigment epithelial cells (RPEs), to conduct a preliminary viability study of RPEs exposed to ABL, and to evaluate the effects of ABL on RPE proliferation and RPE-mediated matrix contraction in vitro.

Methods: Using cultured bovine RPEs, immunohistochemistry was used to study ABL binding. Morphologic and trypan blue exclusion techniques were used for toxicity studies.

Does Psi exist? Lack of replication of an anomalous process of information transfer.

D. J. Bem and C.

Recognizing through feeling. A physical and computer simulation based on educational theory.

This article focuses on the educational theory underpinning computer-based simulation in professional education. An innovative computer-based physical simulation to facilitate student learning of assessment and palpation skills in midwifery has been developed to prototype stage and preliminary evaluations conducted. The learning experience explicitly builds on the learning and teaching theory--a "conversational framework"--developed by Laurillard.

Edible mushroom (Agaricus bisporus) lectin, which reversibly inhibits epithelial cell proliferation, blocks nuclear localization sequence-dependent nuclear protein import.

The Galbeta1-3GalNAcalpha (TF antigen)-binding lectin (ABL) from the common edible mushroom (Agaricus bisporus) has a potent anti-proliferative effect without any apparent cytotoxicity. This unusual combination of properties prompted investigation of its mechanism of action. In contrast to soluble lectin, agarose-immobilized, and hence noninternalizable ABL had no effect on proliferation of HT29 colon cancer cells.

Biaryl acids: novel non-nucleoside inhibitors of HIV reverse transcriptase types 1 and 2.

A series of biaryl acids has been found to show micromolar inhibition of the HIV reverse transcriptase (RT) from types 1 and 2 with IC50S in the micromolar range. The series was discovered by consideration of the polymerase active site and sub-structure searching of the company compound collection. Synthesis of analogues to investigate the SAR is described.

Pancreatic tumour marker anti-mucin antibody CAM 17.1 reacts with a sialyl blood group antigen, probably I, which is expressed throughout the human gastrointestinal tract.

CAM 17.1 is an antimucin monoclonal antibody which has recently been proven valuable as a reagent for serological diagnosis of pancreatic cancer. A series of studies have been performed to characterise its epitope.

Learning with technology: use of case-based physical and computer simulations in professional education.

This presentation will clarify contemporary ideas on the role of technology in education and how it can be employed to improve student learning experiences and outcomes. The paper will emphasise RMIT's role in providing quality education that is relevant to today's world and professional practice. It will examine a specific collaborative (RMIT & ACU), interdisciplinary project 'Pregnancy Simulator: Developing and Enhancing Student Learning of Assessment Skills'.

Learning with technology: use of case-based physical and computer simulations in professional education.

This paper describes a multimedia technology project in midwifery education and how it is being developed to improve student learning experiences and outcomes. The role of the university providing quality education relevant to today's world and professional practice is emphasised. A collaborative (Royal Melbourne Institute of Technology and Australian Catholic University) interdisciplinary project 'Pregnancy Simulator: Developing and Enhancing Student Learning of Pregnancy Assessment Skills' was developed with university and direct Commonwealth support.

Resonance effect for neural spike time reliability.

The spike timing reliability of Aplysia motoneurons stimulated by repeated presentation of periodic or aperiodic input currents is investigated. Two properties of the input are varied, the frequency content and the relative amplitude of the fluctuations to the mean (expressed as the coefficient of variation: CV). It is shown that, for small relative amplitude fluctuations (CV approximately 0.

Can animals detect when their owners are returning home? An experimental test of the 'psychic pet' phenomenon.

In his book, Seven Experiments That Could Change The World, Rupert Sheldrake suggested that the public carry out experiments to test whether pets can psychically detect when their owners are returning home. The first of these tests was undertaken by an Austrian television company and involved an owner in the north-west of England, Pam Smart (PS) and her dog (Jaytee). The test appeared remarkably successful and seemed to show Jaytee responding when PS set off to return home from a remote location.