Solubilisation, partial purification and properties of acyl-CoA: glycerol-3-phosphate acyltransferase from avocado (Persea americana) fruit mesocarp.

Glycerol-3-phosphate acyltransferase (G3PAT) activity was studied using a microsomal membrane fraction from avocado (Persea americana) mesocarp. G3PAT was shown to be an integral membrane protein, having an active site that appeared to be accessible to the cytoplasmic face of the endoplasmic reticulum, in experiments using limited proteolytic digestion. CHAPS solubilisation (0.

Monomeric human cathepsin E.

Cathepsin E is a homodimer, consisting of two monomers linked by an inter-molecular disulphide bond. The cysteine residue involved is located near to the N-terminus of the mature proteinase. By mutating this residue to alanine, a monomeric form of human cathepsin E was engineered and purified.

Electronmicroscopic investigation of the effects of biocides on Pseudomonas aeruginosa PAO bacteriophage F116.

Electronmicroscopy was used to observe morphological changes of the Pseudomonas aeruginosa PA0 bacteriophage F116 when treated with various biocides commonly used as antibacterial and antifungal agents. Because of its large size (145 nm) and its organised structure (an isometric head and a tail), it was possible to classify structural damage into eight categories. The morphological changes induced depended on the type of biocide used and its concentration.

Energy dispersive analysis of X-rays study of the distribution of chlorhexidine diacetate and cetylpyridinium chloride on the Pseudomonas aeruginosa bacteriophage F116.

Using an energy dispersive analyser of X-rays fitted to a scanning electron microscope, chlorhexidine was shown not to bind onto F116 bacteriophage, unlike cetylpyridinium chloride, which possibly penetrated the phage. This could explain the difference in viricidal activity between the two compounds.

X-ray microanalysis of chlorhexidine-treated cells of Saccharomyces cerevisiae.

The use of energy dispersive analysis of X-rays (EDAX) to identify and quantify the presence of chlorhexidine diacetate (CHA) within Saccharomyces cerevisiae cells was examined. Chlorine was used as the elemental marker tag. Saccharomyces cerevisiae cells exposed to 1000 micrograms ml-1 CHA took up increasing amounts of CHA over a time period of 30 s to 30 min.

The effect of contrast adaptation on briefly presented stimuli.

Wilson and Humanski (1993) have recently reported evidence that adapting to low temporal frequency sinewave gratings yields little threshold elevation for briefly presented test stimuli. We postulated that brief stimuli may be detected by a transient channel which would be minimally affected by a low temporal frequency adapting pattern. We therefore measured the effect of adaptation on briefly presented test stimuli for a wider range of adapting temporal frequencies.

Expectations as determinants of patient satisfaction: concepts, theory and evidence.

The apparent lack of conceptual agreement and the inconsistency in the approach to understanding expectations prompted this analysis of the literature in the field of patient satisfaction. A review of 18 journals over the last few years, as well as a number of relevant books, provided the evidence for the state of the current theory. An attempt has been made to distill the main definitions in use, to illustrate practical models of the relationship between expectations and satisfaction, to identify the influential personal and social variables, and to consider the special nature of health care.

Stress protection due to external fixation.

Bone is sensitive to mechanical influences. The presence of an orthopaedic device will impose constraints on the mechanical environment that may influence subsequent remodelling and repair. An Oxford External Fixator was applied to six intact ovine tibiae.

Highly sensitive detection of fungal antigens by ultrasound-enhanced latex agglutination.

Treatment with ultrasound has been employed to greatly enhance the sensitivity of commercially available latex agglutination tests for fungal antigens. This 5 min procedure detects 40 pg ml-1 of Candida albicans mannan and 70 pg ml-1 of Aspergillus fumigatus galactomannan, a 250 and 500-fold improvement respectively over conventional agglutination test sensitivities. The ultrasound-enhanced test offers the possibility of improved diagnosis and management of patients with systemical candidosis or invasive aspergillosis.

Isolation and characteristics of a steady-state visually-evoked potential in humans related to the motion of a stimulus.

We have examined the visual potential evoked by two motion stimuli. In the first stimulus (termed coherent motion) a random-dot pattern oscillated between phases of coherent and incoherent ("snowstorm") motion, and in the second a random-dot pattern alternated in direction of motion (termed direction change). We found that the response to the coherent motion stimulus is low-pass with respect to speed, has low contrast sensitivity and increases steadily with the contrast of the stimuli.

Gamma-hydroxybutyrate promotes oscillatory activity of rat and cat thalamocortical neurons by a tonic GABAB, receptor-mediated hyperpolarization.

The actions of gamma-hydroxybutyrate, a drug known to lead to an increase in nocturnal slow wave sleep and induce epileptic states following systemic application, on the membrane properties of thalamocortical neurons from brain slices of the rat and cat dorsal lateral geniculate nucleus were studied using sharp electrode intracellular recordings. Gamma-hydroxybutyrate applied by addition to the perfusion medium led to a concentration-dependent and reversible hyperpolarization of the membrane potential accompanied by a decrease in apparent input resistance (0.1 mM: 2.

Age effects in the processing of typical and distinctive faces.

Two experiments exploring the differential processing of distinctive and typical faces by adults and children are reported. Experiment 1 employed a recognition memory task. On three out of four dimensions of measurement, children of 5 years of age did not show an advantage for distinctive faces, whereas older children and adults did.

Simultaneous detection of amplicon and HSV-1 helper encoded proteins reveals that neurons and astrocytoma cells do express amplicon-borne transgenes in the absence of synthesis of virus immediate early proteins.

HSV-1 amplicon vectors were used to express either a cytoplasmic (beta-galactosidase) or a membrane targeted protein (TIMP-Thy1) in primary neuronal cultures, and a human astrocytoma cell line. Whereas some cells became infected by vector particles alone others were simultaneously infected by both vector and helper particles. Our results show that IEHCMV and HSV-1 IE3 promoters are able to direct transgene expression in these cells in the absence of synthesis of helper virus transacting proteins, and stress the need of monitoring expression from both partners of an amplicon population, in order to differentiate transgene expression in cells singly infected with amplicon particles, from those infected by both amplicon and helper particles.

Management of veterinary wounds.

A comparison is made between the management of human and animal wounds. Wounds should be classified in order to aid the selection of the most appropriate form of treatment. The concept of the 'golden period' is now less accepted and effective early surgical treatment is advocated.

Immunolocalisation of protein phosphatase inhibitor-1 in the cerebral cortex of the rat, cat and ferret.

The distribution of inhibitor-1 was analysed in the neocortex of cat, ferret and rat by immunocytochemistry (at the light and electron microscope levels) and by immunoblotting using an affinity purified antibody which recognises both the phosphorylated and dephosphorylated forms of the protein. In each mammalian cortex immunocytochemical techniques identified inhibitor-1 predominantly in infragranular pyramidal neurons and, at a lower concentration, in supragranular pyramidal neurons of cortical layers II-III, and V-VI. Within the cortical layers, neuronal cell bodies and apical dendrites were stained strongly but no immunoreactivity was associated with dendritic spines.

A temperature-compensated ultradian clock ticks in Schizosaccharomyces pombe.

An ultradian oscillation is described for Schizosaccharomyces pombe which meets the criteria for a cellular clock, i.e. timekeeping device.

Supernormal conditioning.

In Experiment 1, rats received an A+AX degrees discrimination in which food was presented after Stimulus A by itself but not after a simultaneous compound of A with Stimulus X. AX was then paired with food in a 2nd stage, followed by test trials with A alone. Responding on the test trials with A was more vigorous than during a control stimulus that had been consistently paired with food.

Effects of context on responding during a compound stimulus.

In 4 experiments, the authors used rats to examine the strength of responding during a clicker-tone compound in the presence of a light, after the auditory stimuli had individually been paired with food in the presence of the same light. Experiment 1 demonstrated a higher rate of responding during the compound when the duration of the light was short rather than long. In Experiments 2, 3, and 4, the long duration light was used as a signal for food in a conditional discrimination involving the tone and the clicker.

Variations in the quality of uncalcified fibrocartilage at the insertions of the extrinsic calf muscles in the foot.

It has been suggested that fibrocartilage at entheses (tendon-bone junctions) prevents collagen fibres bending at the hard tissue interface. We have investigated this function by exploring the relationship between the presence or amount of fibrocartilage at the attachments of the major extrinsic muscles in the foot, and the extent to which these tendons bend near their entheses during movement. The tendons were taken from each of 5 formalin-fixed dissecting room cadavers and prepared for routine histology, and sections were collected systematically throughout the blocks.

Expression of biologically active procorticotrophin-releasing hormone (proCRH) in stably transfected CHO-K1 cells: characterization of nuclear proCRH.

Corticotrophin-releasing hormone (CRH) is a 41 amino acid neuropeptide which is cleaved at a pair of dibasic amino acids from a larger precursor molecule (pre-proCRH) by the action of endopeptidases. In cells possessing a regulated secretory pathway, sorting of proneuropeptides and prohormones occurs within the trans-Golgi network, where they are finally packaged into secretory vesicles to be released in response to an external stimulus. Such cells also possess a constitutive secretory pathway, and neuropeptides are also translocated into this subcellular compartment.

Synaptogenesis and distribution of presynaptic axonal varicosities in low density primary cultures of neocortex: an immunocytochemical study utilizing synaptic vesicle-specific antibodies, and an electrophysiological examination utilizing whole cell recording.

Low-density primary cultures of neocortical neurons were utilized to examine: (i) early interactions of growing neurites with morphological characteristics of axons with other neuronal elements, and (ii) the distribution of presynaptic axonal varicosities closely apposed to MAP-2 immunoreactive, putatively postsynaptic, dendrites. At the light microscopical level axonal varicosities, presumably presynaptic terminals, were identified using immunocytochemistry incorporating antibodies specific for the synaptic vesicle antigens synaptophysin and synapsin. The presence of synaptophysin- and synapsin-immunoreactive swellings along axonal processes was first detected at 5 days post-plating and was also apparent in axons growing in isolation.

The in vitro characterization and biostability of 99mTc-dextran and its accumulation within the inflamed paws of adjuvant-induced arthritic rats.

The in vitro and in vivo stability in normal and adjuvant-induced arthritic rats of 99mTc-dextrans (10, 40 and 500 kDa) have been investigated. The circulation half-lives were molecular weight dependent, with 10 and 40 kDa fractions being cleared relatively rapidly due to their ability to cross the glomerular basement membrane. The 500 kDa dextran was eliminated more slowly although 79% had been removed from the circulation 4 h post injection which probably was due to its degradation by dextranases and subsequent glomerular excretion.

Functional characteristics of the inner voice and the inner ear: single or double agency?

Double agency theories of short-term memory posit the functional independence of a phonological store (inner ear) and articulatory process (inner voice). A series of 5 experiments challenges this view. Articulatory suppression during retention of 9-item lists gives rise to a changing-state effect similar to that shown for irrelevant speech.

Use of prior beliefs in the assignment of causal roles: causal powers versus regularity-based accounts.

There is a tradition of models of causal judgment in which causes and other causal roles are defined and identified in terms of empirical patterns of association with effects. In the present experiments, results conflicting with the predictions of such models were obtained. In one experiment, subjects judged that an interpretation in which a factor constantly present was identified as the cause was more likely than was an interpretation in which a perfect positive covariate was identified as the cause.