A role for the dominant thalamus in language? A linguistic comparison of two cases subsequent to unilateral thalamotomy procedures in the dominant and non-dominant hemispheres

Background: Thalamotomy has been reported to be successful in ameliorating the motor symptoms of tremor and/or rigidity in people with Parkinson's disease (PD), emphasising the bona fide contribution of this subcortical nucleus to the neural circuitry subserving motor function. Despite evidence of parallel yet segregated associative and motor cortico-subcortical-cortical circuits, comparatively few studies have investigated the effects of this procedure on cognitive functions. In particular, research pertaining to the impact of thalamotomy on linguistic processes is fundamentally lacking. Aims: The purpose of this research was to investigate the effects of thalamotomy in the language dominant and non-dominant hemispheres on linguistic functioning, relative to operative theoretical models of subcortical participation in language. This paper compares the linguistic profiles of two males with PD, aged 75 years (10 years of formal education) and 62 years (22 years of formal education), subsequent to unilateral thalamotomy procedures within the language dominant and non-dominant hemispheres, respectively. Methods & Procedures: Comprehensive linguistic profiles comprising general and high-level linguistic abilities in addition to on-line semantic processing skills were compiled up to 1 month prior to surgery and 3 months post-operatively, within perceived on'' periods (i.e., when optimally medicated). Pre- and post-operative language performances were compared within-subjects to a group of 16 non-surgical Parkinson's controls (NSPD) and a group of 16 non-neurologically impaired adults (NC). Outcomes & Results: The findings of this research suggest a laterality effect with regard to the contribution of the thalamus to high-level linguistic abilities and, potentially, the temporal processing of semantic information. This outcome supports the application of high-level linguistic assessments and measures of semantic processing proficiency to the clinical management of individuals with dominant thalamic lesions. Conclusions: The results reported lend support to contemporary theories of dominant thalamic participation in language, serving to further elucidate our current understanding of the role of subcortical structures in mediating linguistic processes, relevant to cortical hemispheric dominance.

A survey of Australian mental health occupational therapists

Mental health reform in the western developed world has resulted in new models of care and changed work practices for all mental health professionals. Occupational therapists, as with other mental health professionals, have been required to assume new roles and responsibilities. Literature from the United Kingdom has reflected concern about this new way of working. The aim of this exploratory study was to examine the current work practices of and issues faced by Australian mental health occupational therapists. One hundred and forty-eight respondents (74%) answered an occupational therapy practice in mental health questionnaire. The results from this survey suggest that there are two quite distinct groups of occupational therapists working in mental health settings in Australia. One group works as rehabilitation therapists in traditional activity-focused work roles. The other group works as case manager therapists and employs a much broader spectrum of clinical and support roles. The issues facing therapists include the development and maintenance of a clearly defined role, generic case management versus discipline-specific roles, recruitment and retention, the need for research and evidence-based practice, professional standing, and education and professional development. The concerns over the role of occupational therapy in mental health were similar to those in previous British studies. The implications of these findings include a need for education and training at the undergraduate and postgraduate levels to equip mental health occupational therapists with both discipline-specific and generic skills.

The differential role of alcohol expectancies, drinking refusal self-efficacy and coping resources in predicting alcohol consumption in community and clinical samples

This study explored the relationship between coping, alcohol expectancies and drinking refusal self-efficacy in predicting drinking behaviour in both community and clinical samples. These variables were found to have differential effects in their association with frequency and volume of alcohol consumption across the two samples. Generally, drinking refusal self-efficacy was a more salient factor in relation to frequency and volume of community drinking, while coping and expectancies were more strongly associated with frequency of drinking sessions by problem drinkers. The interaction between expectancies and drinking refusal self-efficacy was related to volume of consumption in both groups, while coping and expectancies interacted in their association with frequency in the clinical group. The findings are discussed with regard to the different patterns of cognitive variables governing the decision to drink and the amount consumed in each drinking session, which may differentiate community and problem drinkers.

Investigation of hip abductor activation in subject with clinical unilateral hip osteoarthritis

Objectives: (a) To compare the magnitude of gluteus medius and tensor fascia lata activation between a group of subjects with clinical unilateral hip osteoarthritis and a group of healthy older adults. (b) To compare the magnitude of activation of the gluteus medius and tensor fascia lata between sides in a group of subjects with clinical unilateral hip osteoarthritis and a group of healthy older adults. Methods: 19 subjects with clinical unilateral hip osteoarthritis and 19 healthy controls were investigated. The subjects performed a stepping task during which recordings were obtained using surface electromyograms from the hip abductors, and kinetic data were obtained from a dual force platform. Results: Subjects with clinical hip osteoarthritis had higher gluteus medius activation than the healthy older adults (p=0.037). In addition, there were no differences in the magnitude of gluteus medius activation between the sides (p=0.733). There was no difference in the force platform data between the groups (p=0.078). Conclusions: The increased magnitude of gluteus medius activation in the group with hip osteoarthritis is evidence of a muscular dysfunction associated with hip disease. This has implications for the progressive nature of the disease and for its conservative management.

A clinical audit of the prescribing of celecoxib and rofecoxib in Australian rural general practice

Aims The new cyclooxygenase-2 (COX-2) selective inhibitors, celecoxib (Celebrex®) and rofecoxib (Vioxx®), have been widely prescribed since their launch. No reviews currently appear in the literature of prescribing patterns in Australia. This paper describes a self-audit of the clinical use of selective COX-2 inhibitor therapy undertaken with rural general practitioners (GPs) in Australia. Methods A structured audit form was developed and distributed to interested GPs. The form was self-administered and focused on issues about COX-2 inhibitors and the types of patients who were receiving them, e.g. indications, patient demographics, risk factors and drug interactions. Results A total of 627 patients were recruited (569 celecoxib and 58 rofecoxib). A range of doses was prescribed. Osteoarthritis was the most common indication (68.1%). Risk factors known for the nonselective nonsteroidal anti-inflammatory drugs were identified in 65.1% of patients, with the most common being advanced age, hypertension and previous peptic ulcer disease. Potential drug interactions were common. A variety of reasons for initiation of therapy was identified; these included perceived increased efficacy, safety and failure of other treatment. Conclusions These results show that COX-2 inhibitors are being prescribed for patients with multiple risk factors that may place the patient at increased risk of adverse drug reactions to a COX-2 inhibitor. The perception of improved safety and efficacy was common and is of concern. Limitations of the study include the reliance on self-reporting.

Postural control and movement performance during upper limb tasks in children with developmental co-ordination disorder (DCD)

At least 6% of primary school aged children present with DCD, where co-ordination is substantially below the normal range for the child’s age and intelligence. Motor skill difficulties negatively affect academic achievement, recreation and activities of daily living. Poor upper-limb co-ordination is a common difficulty for children with DCD. A possible cause of this problem is deviant muscle timing in proximal muscle groups, which results in poor postural and movement control. While studies have been published investigating postural control in response to external perturbations, detail about postural muscle activity during voluntary movement is limited even in children with normal motor development. No studies have investigated the relationship between muscle timing, resultant arm motion and upper-limb coordination deficits. Objectives: To investigate the relationship between functional difficulties with upper-limb motor skills and neuromuscular components of postural stability and coordination. Specifically, to investigate onset-timing of muscle activity, timing of arm movement, and resultant three-dimensional (3D) arm co-ordination during rapid, voluntary arm movement and to analyse differences arising due to the presence of DCD. This study is part of a larger research program investigating postural stability and control of upper limb movement in children. Design: A controlled, cross-sectional study of differences between children with and without DCD. Methods: This study included 50 children aged eight to 10 years (25 with DCD and 25 without DCD). Children participated in assessment of motor skills according to the Movement ABC Test and a laboratory study of rapid, voluntary arm movements. Parameters investigated included muscle activation timing of shoulder and trunk muscles (surface electromyography), arm movement timing (light sensor) and resultant 3D arm motion (Fastrak). Results: A MANOVA is being used to analyse between-group differences. Preliminary results indicate children with DCD demonstrate altered muscle timing during a rapid arm raise when compared with the control group of children. Conclusion: Differences in proximal muscle timing in children with DCD support the hypothesis that altered proximal muscle activity may contribute to poor proximal stability and consequently poor arm movement control. This has implications for clinical physiotherapy.

Assessing clinical reasoning: a method to monitor its development in a PBL curriculum

The aim of this study was to develop and trial a method to monitor the evolution of clinical reasoning in a PBL curriculum that is suitable for use in a large medical school. Termed Clinical Reasoning Problems (CRPs), it is based on the notion that clinical reasoning is dependent on the identification and correct interpretation of certain critical clinical features. Each problem consists of a clinical scenario comprising presentation, history and physical examination. Based on this information, subjects are asked to nominate the two most likely diagnoses and to list the clinical features that they considered in formulating their diagnoses, indicating whether these features supported or opposed the nominated diagnoses. Students at different levels of medical training completed a set of 10 CRPs as well as the Diagnostic Thinking Inventory, a self-reporting questionnaire designed to assess reasoning style. Responses were scored against those of a reference group of general practitioners. Results indicate that the CRPs are an easily administered, reliable and valid assessment of clinical reasoning, able to successfully monitor its development throughout medical training. Consequently, they can be employed to assess clinical reasoning skill in individual students and to evaluate the success of undergraduate medical schools in providing effective tuition in clinical reasoning.

Randomisation in clinical trials

Randomisation is the process of assigning clinical trial participants to treatment groups. Randomisation gives each participant a known (usually equal) chance of being assigned to any of the groups. Successful randomisation requires that group assignment cannot be predicted in advance.

Clinical pathways in mental health

Caremaps [Clinical pathways] are like microwave ovens: five years from now, members of all disciplines will marvel at how they ever got along without them. Of course there will always be some that refuse to accept innovation or who are technophobic. Most people, however, will readily incorporate useful, practical new products into their daily lives.' Zander [1]

Community-acquired Klebsiella pneumoniae bacteremia: Global differences in clinical patterns

We initiated a worldwide collaborative study, including 455 episodes of bacteremia, to elucidate the clinical patterns of Klebsiella pneumoniae. Historically, community-acquired pneumonia has been consistently associated with K. pneumoniae. Only four cases of community-acquired bacteremic K. pneumoniae pneumonia were seen in the 2-year study period in the United States, Argentina, Europe, or Australia; none were in alcoholics. In contrast, 53 cases of bacteremic K. pneumoniae pneumonia were observed in South Africa and Taiwan, where an association with alcoholism persisted (p=0.007). Twenty-five cases of a distinctive syndrome consisting of K. pneumoniae bacteremia in conjunction with community-acquired liver abscess, meningitis, or endophthalmitis were observed. A distinctive form of K. pneumoniae infection, often causing liver abscess, was identified, almost exclusively in Taiwan.

A novel bioassay for human somatogenic activity in serum samples supports the clinical reliability of immunoassays

OBJECTIVE Because there is discordance between different immunoassay values for serum hGH, and because clinical state may not correlate with immunoreactive hGH, we have developed an assay to accurately measure serum hGH somatogenic bioactivity. The results of this assay were compared with the Elegance two-site ELISA assay across 135 patient samples in a variety of clinical states. DESIGN The somatogenic assay was based on stable expression of hGH receptor in the murine BaF line, allowing these cells to proliferate in response to hGH. To eliminate interference by other growth factors in serum, we created a specific antagonist of the hGH receptor (similar to Trovert or Pegvisomant) which allowed us to obtain a true measure of hGH somatogenic activity by subtraction of the activity in the presence of the antagonist. The assay was carried out in microtiter plates over 24 h, with oxidation of a chromogenic tetrazolium salt (MTT) as the endpoint. PATIENTS These encompassed a number of different clinical conditions related to short stature, including idiopathic short stature, neurosecretory dysfunction and renal failure, as well as obese patients on dietary restriction and normal volunteers. MEASUREMENTS In addition to the colourimetric (MTT) response to hGH, we measured free hGH by stripping out GHBP-bound hGH using beads coupled to a monoclonal antibody to the GHBP (GH binding protein). All samples were measured in both bioassay and ELISA assay. RESULTS This bioassay was sensitive (5 mU/l or 2 mug/l) and precise, and not subject to interference by the GHBP. There was a good correlation (r = 0.95) between bioactivity and immunoactivity across clinical states. There was, however, an increased bioactivity during secretory peaks (over 25 mU/l), which has been reported previously for the Nb2 bioassay. Free hGH did not correlate with clinical state. CONCLUSIONS Because the results of the Elegance ELISA and the bioassay correlate well, even though there is greater bioactivity at higher hormone concentrations, it is evident that an appropriate immunoassay is able to act as a reliable indicator for clinical assessment. In those rare cases where bio-inactive GH exists, our bioassay should provide an appropriate means to demonstrate this.