Assessment and management of dysphagia following pharyngolaryngectomy with free jejunal interposition: A series of eight case studies

The physiological and structural deficits contributing to swallowing complications in the pharyngolaryngectomy patient population are not homogeneous. Consequently, a team approach, involving medical investigations as well as clinical and radiological assessments of swallowing, is necessary to facilitate diagnosis of the underlying impairment and assist the medical/surgical and speech pathology team members in the process of individualizing the management plan for each patient. In the present study, the clinical assessment and management of eight pharyngolaryngectomy patients who presented with a decline in swallowing function unrelated to immediate postsurgical effects or direct effects of radiotherapy are reported. Clinical and radiological investigations revealed a heterogeneous group of factors contributing to their swallowing impairments and disability levels, including difficulty with graft and anastomotic patency and graft motility, impaired lingual coordination, increased bolus transit time, nasal and oral regurgitation, patient distress, and recurrence. Variation between the cases supported the need for differential intervention and management plans for all eight patients. Ratings of perceived swallowing disability, handicap, and well-being/distress levels at initial assessment and again six months following dysphagia intervention revealed a pattern of reduced levels of impairment, functional disability, and overall patient distress levels following informed intervention. The present case study data highlights the key role thorough clinical and radiological investigations play in the process of diagnosing the factors contributing to dysphagia and guiding the management of the resultant swallowing disability in the pharyngolaryngectomy population.

Peripheral T-Cell tolerance defined through transgenic mouse studies

Selection in the thymus restricted by MHC and self-peptide shapes the diverse reactivities of the T-cell population which subsequently seeds into the peripheral tissues, in anticipation of the universe of pathogen antigens to which the organism may be exposed. A necessary corollary is the potential for T-cell self-reactivity (autoimmunity) in the periphery. Transgenic mouse models in which transgene expression in the thymus is prevented or excluded, have been particularly useful for determining the immunological outcome when T-cells encounter transgene-encoded 'self' antigen in peripheral tissues. Data suggest that non-mutually exclusive mechanisms of T-cells 'ignoring' self-antigen, T-cell deletion, T-cell anergy and T-cell immunoregulation have evolved to prevent self-reactivity while maintaining T-cell diversity. The peripheral T-cell repertoire, far from being static following maturation through the thymus, is in a dynamic stated determined by these peripheral selective and immunoregulatory influences. This article reviews the evidence with particular reference to CD8+ive T-cells.

Maturation studies of pecan nuts grown in Queensland

Changes in chemical composition, physical and sensory characteristics were followed in two pecan cultivars Wichita and Western Schley harvested from a commercial orchard at Gatton in Queensland seven times during 1996. Testa colour of both pecan cultivars darkened and opalescence decreased as the nuts matured. Bitterness of Western Schley pecans decreased with maturity. Colour of shuck, shell and kernel of both cultivars developed as the nuts matured. Wichita pecans were larger than Western Schley at all harvest times. Both nut-in-shell and kernel moisture decreased with maturity, whereas oil and sucrose contents increased. Both pecan cultivars had reached advanced maturation by the first harvest on March 18.

It's the first bites that count: Survival of first-instar monarchs on milkweeds

Mortality of first instars is generally very high, but variable, and is caused by many factors, including physical and chemical plant characters, weather and natural enemies. Here, a summary of detailed field-based studies of the early-stage survival of a specialist lepidopteran herbivore is presented. First-instar larvae of the monarch butterfly, Danaus plexippus, a milkweed specialist, generally grew faster and survived better on leaves when latex flow was reduced by partial severance of the leaf petiole. The outcome depended on milkweed species, and was related to the amount of latex produced, as well as other plant characters, such as leaf hairs, microclimate and concentration of secondary metabolites. Even for a so-called 'milkweed specialist', larval performance and survival appears to be related to the concentration of cardenolides produced by the plants (a potential chemical defence against herbivory). This case study of monarchs and milkweeds highlights the need for field-based experiments to assess the effect of plant characters on the usually poor survival of early instar phytophagous insects. Few similar studies concerning the performance and survival of first-instar, eucalypt-specific herbivores have been conducted, but this type of study is considered essential based on the findings obtained using D. plexippus.

Influence of fungal pathogens and environmental conditions on disease severity, flower fall and desiccation of harvested Geraldton waxflower - 2. Studies with commercial packages

Relationships were examined between environmental conditions mediated by packaging and handling and the deterioration of harvested Geraldton waxflower cv. 'Fortune Cookie'. Disease severity plus flower and leaf drop caused by inoculation with Botrytis cinerea were reduced by lowering handling temperatures to 0, 5 or 5/20 degreesC alternated daily, versus 20 degreesC. They were also reduced by inhibition of ethylene action with a silver thiosulfate pulse pretreatment. Additionally, treatments that enhanced water loss, such as packing dry, keeping forced air-cooling holes open and strategic placement of extra ventilation holes may also reduce disease severity and flower plus leaf fall. Inclusion of KMnO4-based Bloomfresh ethylene scrubbing sachets in packages did not reduce disease severity or lessen flower plus leaf fall. Thus, deterioration of waxflower packaged in commercial cartons can be minimised by keeping temperatures low, packing plant material dry, use of cartons with strategically placed ventilation holes and/or pretreatment with silver thiosulfate.

Television and cultural studies: Unfinished business

This introductory article argues that the current state of debate on television within cultural studies is marked by considerable areas of theoretical and political uncertainty. The spread of deregulatory and privatizing public policies in relation to television, and the disarticulation of television from the idea of the national community and from the role of the citizen, have posed new problems for theorizing the relation between television and its audiences. In this article I survey a number of key areas of debate: the relation between television, the nation and the state; television and the citizen/consumer, television content and performance, and the likely future(s) of television.

An improved survival model of hypoxia/ischaemia in the piglet suitable for neuroprotection studies

The purpose of this study, was to develop a newborn piglet model of hypoxia/ischaemia which would better emulate the clinical situation in the asphyxiated human neonate and produce a consistent degree of histopathological injury following the insult. One-day-old piglets (n = 18) were anaesthetised with a mixture of propofol (10 mg/kg/h) and alfentinal (5,5.5 mug/kg/h) i.v. The piglets were intubated and ventilated. Physiological variables were monitored continuously. Hypoxia was induced by decreasing the inspired oxygen (FiO(2)) to 3-4% and adjusting FiO(2) to maintain the cerebral function monitor peak amplitude at less than or equal to5 muV. The duration of the mild insult was 20, min while the severe insult was 30 min which included 10 min where the blood pressure was allowed to fall below 70% of baseline. Control piglets (n=4 of 18) were subjected to the same protocol except for the hypoxic/ischaemic insult. The piglets were allowed to recover from anaesthesia then euthanased 72 It after the insult. The brains were perfusion-fixed, removed and embedded in paraffin. Coronal sections were stained by haematoxylin/eosin. A blinded observer examined the frontal and parietal cortex, hippocampus, basal ganglia, thalamus and cerebellum for the degree of damage. The total mean histology score for the five areas of the brain for the severe insult was 15.6 +/-4.4 (mean +/-S.D., n=7), whereas no damage was seen in either the mild insult (n=4) or control groups. This 'severe damage' model produces a consistent level of damage and will prove useful for examining potential neuroprotective therapies in the neonatal brain. (C) 2001 Elsevier Science BY. All rights reserved.

A multi-purpose rainfall simulator for field infiltration and erosion studies

This paper describes a rainfall simulator developed for field and laboratory studies that gives great flexibility in plot size covered, that is highly portable and able to be used on steep slopes, and that is economical in its water use. The simulator uses Veejet 80100 nozzles mounted on a manifold, with the nozzles controlled to sweep to and from across a plot width of 1.5 m. Effective rainfall intensity is controlled by the frequency with which the nozzles sweep. Spatial uniformity of rainfall on the plots is high, with coefficients of variation (CV) on the body of the plot being 8-10%. Use of the simulator for erosion and infiltration measurements is discussed.

Adjusting for fat-free mass in metabolic studies

in a recent publication, Eriksson et al. [1] explored the relationship between size at birth and resting metabolic rate and body composition in adulthood in a cohort of over 300 men and women. They reported an unexpected finding that people of both sexes who had a low birth weight also had a higher metabolic activity per unit muscle tissue. This conclusion was drawn from an analysis where resting metabolic rate (expressed as kcal/kg fat-free mass) in adulthood was examined relative to the birth weight of the subject. One explanation that they suggested was that the apparent increased activity of muscle tissue resulted from an increased sympathetic drive associated with low birth weight. There may be a less physiological reason for the findings of Eriksson et al. Whilst the data are not given specifically in the text, it can be seen clearly from Fig. 1 in the paper that the mean fat-free mass measured in adulthood increased, in both sexes, from the lightest birth weight group to the heaviest birth weight group when the cohort were divided into tertiles based on birth weight. The crux of the issue is that in many - indeed most - cases, expressing resting energy expenditure as kcal/kg fat-free mass does not totally adjust for fat-free mass [2 - 5], and a bias is introduced so that those who have a higher fat-free mass will tend to have a lower resting energy expenditure when expressed per kg fat-free mass. This bias found when expressing many physiological parameters relative to body size, body weight or body composition has long been known [6], and should be carefully considered by appropriate adjustment and hence analysis.