Homeostatic competition among T cells revealed by conditional inactivation of the mouse Cd4 gene

Absence of CD4 impairs the efficiency of T cell receptor (TCR) signaling in response to major histocompatibility complex (MHC) class II-presented peptides. Here we use mice carrying a conditional Cd4 allele to study the consequences of impaired TCR signaling after the completion of thymocyte development. We show that loss of CD4 decreases the steady-state proliferation of T cells as monitored by in vivo labeling with bromo-deoxyuridine. Moreover, T cells lacking CD4 compete poorly with CD4-expressing T cells during proliferative expansion after transfer into lymphopenic recipients. The data suggest that T cells compete with one another during homeostatic proliferation, and indicate that the basis of this competition is TCR signaling.

A double-blind, randomized, prospective evaluation of the efficacy and safety of risperidone versus haloperidol in the treatment of schizoaffective disorder

The relative efficacy and safety of risperidone versus haloperidol in the treatment of schizoaffective disorder was studied. Sixty-two patients (29 depressed type; 33 bipolar type) entered a three-site, randomized, double-blind, 6-week trial of risperidone (up to 10 mg/day) or haloperidol (up to 20 mg/day). Trained raters assessed baseline, weekly, and end-of-study levels of psychopathology with the Positive and Negative Syndrome Scale (PANSS), the 24-item Hamilton Rating Scale for Depression (HAM-D-24) and the Clinician-Administered Rating Scale for Mania (CARS-M). The authors were unable to statistically distinguish between risperidone and haloperidol in the amelioration of psychotic and manic symptoms. In addition, there was no difference in worsening of mania between the two agents in either subgroup (i.e., depressed or bipolar subgroups). For the total PANSS, risperidone produced a mean decrease of 16 points from baseline compared with a 14-point decrease with haloperidol. For the total CARS-M scale, risperidone and haloperidol produced mean change scores of 5 and 8 points, respectively, and for the CARS-M Mania subscale, 3 and 7 points, respectively. Additionally, risperidone produced a mean decrease of 13 points from the baseline 24-item HAM-D, compared with an 8-point decrease with haloperidol. In those patients who had more severe depressive symptoms (i.e., HAM-D baseline score >20), risperidone produced at least a 50% mean improvement in 12 (75%) of 16 patients in comparison to 8 (38%) of 21 patients receiving haloperidol. Haloperidol produced significantly more extrapyramidal side effects and resulted in more dropouts caused by any side effect. There was no difference between risperidone and haloperidol in reducing both psychotic and manic symptoms in this group of patients with schizoaffective disorder. Risperidone did not demonstrate a propensity to precipitate mania and was better tolerated than haloperidol. In those subjects with higher baseline HAM-D scores (i.e., >20), risperidone produced a greater improvement in depressive symptoms than haloperidol.

Rehabilitation outcomes for brain injured patients in Australia: functional status, length of stay and discharge destination

This study describes the rehabilitation length of stay (LOS), discharge destination and discharge functional status of 149 patients admitted with traumatic brain injury (TBI) to an Australian hospital over a 5-year period. Hospital charts of patients admitted between 1993-1998 were reviewed. Average LOS over the 5-year time period was 61.8 days and only decreased nominally over this time. Longer LOS was predicted by lower admission motor FIM scores and presence of comorbidities. Mean admission and discharge motor FIM scores were 58 and 79, which represented a gain of 21 points. Higher discharge motor FIM scores were predicted by higher admission motor FIM scores and younger age. FIM gain was predicted by cognitive status and age. Most patients, 88%, were discharged back to the community, with 30% changing their living setting or situation. Changing living status was predicted by living alone and having poorer functional status on admission.

Improving patient recruitment to multicentre clinical trials: the case for employing a data manager in a district general hospital-based oncology centre

One of the most frequently cited reasons for poor recruitment to multicentre randomized clinical trials is the additional workload placed on clinical staff. We report the effect on patient recruitment of employing a data manager to support clinical staff in an English district general hospital (DGH). In addition, we explore the effect data managers have on the quality of data collected, proxied by the number of queries arising with the trial organizers. We estimate that the cost of employing a data manager on a full-time basis is 502 per patient recruited but may amount to 326 if the appointment is part-time. Data quality is high when full responsibility lies with a data manager but falls when responsibility is shared. Whether the costs of employing a data manager to recruit patients from a DGH are worth incurring depends on the value placed on the speed at which multicentre trials can be completed, how important it is to broaden the research base beyond the traditional setting of teaching hospitals, and the amount of evaluative data required.

Effects of calorie and fluid intake on adverse events during hemodialysis

PURPOSE

To investigate the incidence of adverse events during hemodialysis treatments as a function of calories and fluid intake.

METHODS

The study period was August 3-26, 1999. Hemodialysis visits were studied. Twenty-three patients receiving hemodialysis during the 2nd shift on Tuesday, Thursday, and Saturday were studied. A total of 166 hemodialysis patient visits were studied. Data collected included: amount of fluid and food consumed, blood pressure levels, and mannitol use during each hemodialysis treatment; and any symptoms that occurred either during or after the dialysis treatment (hypotension, nausea, vomiting, diarrhea, cramping, and access problems).

RESULTS

Using regression analysis, calories and fluids were strong predictors of both hypotension (P =.003) and mannitol use (P =.000), but not of cramping or access problems. Patients were 3 times more likely to have hypotension if taking any fluids (P =.011). Patients consuming >200 calories were 2 times as likely to have hypotension (P =.058). Patients were 5 times more likely to use mannitol if taking any fluids (P =.005). Mannitol use increased significantly (P =.001) with those patients consuming >200 calories.

CONCLUSION

Patients who ate more than 200 calories and consumed more than 200 mL of fluid during hemodialysis had an increased incident of hypotensive events and increased use of mannitol.

Development, reliability, and concurrent validity of the modified inventory of potential reconstructive needs

Documentation of burn sequelae can be a difficult and time-consuming task. To date a reliable and systematic format for recording postburn trauma is lacking. The purpose of this research was two-fold: first, to develop a Modified Inventory of Potential Reconstructive Needs from the original Inventory of Potential Reconstructive Needs to allow methodical documentation of functional and cosmetic burn sequelae in all body surface areas of children with burns and, second, to establish interrater reliability and concurrent validity of the instrument, thus allowing its clinical application. Two raters scored the Modified Inventory of Potential Reconstructive Needs on 41 children with a range of burns types and severity. Excellent interrater reliability was demonstrated for both total (intraclass correlation coefficient = 0.996) and subsection inventory scores. Concurrent validity was also established with total scores showing strong positive correlations (0.73-0.76) with three indicators of burn severity. These findings provide initial support for the tool's clinical applicability, particularly in relation to rehabilitative planning and documentation.

Impaired survival of T helper cells in the absence of CD4

Signal transduction in response to ligand recognition by T cell receptors regulates T cell fate within and beyond the thymus. Herein we examine the involvement of the CD4 molecule in the regulation of T helper cell survival. T helper cells that lack CD4 expression are prone to apoptosis and show diminished survival after adoptive transfer to irradiated recipients. The helper lineage in CD4(-/-) animals shows a higher than normal apparent rate of cell division and is also enriched for cells exhibiting a memory cell phenotype. Thus the data point to a necessary role for CD4 in the regulation of T helper cell survival and homeostasis.

A longitudinal subspecialty experience for internal medicine residents

OBJECTIVE

Market and technology innovations have greatly changed the teaching and practice of medicine in the past 10 years. This report describes an innovation in the ambulatory education of internal medicine residents: a subspecialty continuity clinic.

METHODS

A subspecialty continuity clinic was developed to improve the training of internal medicine residents in caring for complex ambulatory patients. The clinic structure is discussed from the perspective of patients, residents, and subspecialists. Logistical challenges and solutions are described.

RESULTS

Two and one-half years into the program, feedback from residents and subspecialists has been positive. In-training examination scores are relatively higher in the involved specialties, and residents are managing illnesses they rarely saw in an outpatient setting before this program.

CONCLUSION

This experience suggests that a subspecialty continuity clinic is worthwhile and practical in educating primary care residents.

Negative regulation of CD4 lineage development and responses by CD5

CD5 deficiency results in a hyper-responsive phenotype to Ag receptor stimulation. Here we show that the development and responses of CD4 lineage T cells are regulated by the function of CD5. Thymocytes expressing the I-Ad-restricted DO11.10 TCR undergo abnormal selection without CD5. In H-2d mice, the absence of CD5 causes deletion of double-positive thymocytes, but allows for efficient selection of cells expressing high levels of the DO11.10 clonotype. By contrast, there is enhanced negative selection against the DO11.10 clonotype in the presence of I-Ab. T cell hybridomas and DO11.10 T cells are more responsive to TCR stimulation in the absence of CD5. Such hypersensitivity can be eliminated by expression of wild-type CD5, but not by a form of CD5 that lacks the cytoplasmic tail. Finally, CD5 deficiency partially suppresses the block of CD4 lineage development in CD4-deficient mice. Taken together, the data support a general role for CD5 as a negative regulator of Ag receptor signaling in the development and immune responses of CD4 lineage T cells.

Knowledge about pain among newly graduated occupational therapists: relevance for curriculum development

In recent years there has been a growing awareness amongst health professionals of the need to prepare undergraduate students more adequately for practice with clients who have pain. Occupational therapists have a central role in enabling such clients to have productive lives despite pain. In this study, an examination was made of the adequacy of preparation for pain practice in graduates from one Australian occupational therapy curriculum. Recent occupational therapy graduates from the University of Queensland, Australia, who responded to a postal survey, obtained an overall 53% correct response rate to a 69-item pain knowledge and attitudes questionnaire. Results indicated the need for further education in this area, especially in the areas of pharmacological management, and pain assessment and measurement. These results were comparable to those obtained from final year occupational therapy students at Dalhousie University in Halifax, Nova Scotia prior to undertaking an elective course about pain. Follow-up interviews with a number of new graduates supported the inclusion of an elective pain course in the undergraduate occupational therapy curriculum at the University of Queensland in Australia.

Assessment of pain perception in clinical practice

With pain a frequent precipitant in individuals seeking manual therapy, it is important for therapists to adequately assess pain. At one level, pain forms an important part of the diagnostic assessment. It is suggested that a simple, reliable and quantitative pain measure be used in patients who present with routine problems. At another level, when the therapist is presented with clients in whom pain does not make sense in terms of its pattern, distribution, history or features, it is advisable to go beyond a simple pain intensity measure.

Thioguanine administered as a continuous intravenous infusion to pediatric patients is metabolized to the novel metabolite 8-hydroxy-thioguanine

Thiopurine antimetabolites have been in clinical use for more than 40 years, yet the metabolism of thiopurines remains only partially understood. Data from our previous pediatric phase 1 trial of continuous i.v. infusion of thioguanine (CIVI-TG) suggested that TG was eliminated by saturable mechanism, with conversion of the drug to an unknown metabolite. In this study we have identified this metabolite as 8-hydroxy-thioguanine (8-OH-TG). The metabolite coeluted with the 8-OH-TG standard on HPLC and had an identical UV spectrum, with a lambda(max) of 350 nm. On mass spectroscopy, the positive ion, single quad scan of 8-OH-TG yielded a protonated molecular ion at 184 Da and contained diagnostic ions at m/z 167, 156, 142, and 125 Da. Incubation of TG in vitro with partially purified aldehyde oxidase resulted in 8-OH-TG formation. 8-OH-TG is the predominant circulating metabolite found in patients receiving CIVI-TG and is likely generated by the action of aldehyde oxidase.

Patients, diagnoses, and procedures in a military internal medicine clinic: comparison with civilian practices

BACKGROUND

Our goal was to compare the demographic features, diagnoses, and procedures in civilian and military ambulatory internal medicine clinics.

METHODS

One year (September 1996 to August 1997) of data from the Ambulatory Data System of the Adult Primary Care Clinic at Madigan Army Medical Center was extracted and compared with the most recent (1995) National Ambulatory Medical Care Survey.

RESULTS

A total of 41,374 Madigan patient encounters were compared with civilian data from the National Ambulatory Medical Care Survey. The age distribution was similar, with military patients averaging 53.5 years of age and civilian patients averaging 54.5 years. Military patients were more likely to be female (71 vs. 60%) and were more ethnically diverse (military: 68% white, 17% African American, 7% Hispanic, 7% Asian American, and 1% Native American; civilian: 78% white, 10% African American, 6% Hispanic, 5.9% Asian American, and 0.3% Native American). There were similar rank orderings of the top 189 diagnostic groups seen in each setting (Spearman's rho = 0.87). There were also no differences in the type or rank order of procedures performed between military and civilian internists (p = 0.53).

CONCLUSION

The practice content of military and civilian practices appears to be more similar than different.

Joslin Vision Network Validation Study: pilot image stabilization phase

PURPOSE

This preliminary study is designed to evaluate the quality of initial images obtained using the Joslin Vision Network (JVN) image capture and retrieval system.

METHODS

Digitized images of 18 patients (36 eyes) were obtained using Topcon Non-mydriatic Fundus Camera and various imaging protocols as described for each series of images. Level of retinopathy ranged from no diabetic retinopathy to proliferative diabetic retinopathy. Images were reviewed and evaluated in comparison to medical record notes and Early Treatment Diabetic Retinopathy Study (ETDRS) seven-standard field stereoscopic 35-mm retinal fundus photographs--when available--to determine the ability of JVN digitized images to allow appropriate diagnosis and clinical management. JVN images were also evaluated for presence of photographic artifacts and stereoscopic presentation. The various displays and relative value of each JVN display were also evaluated.

RESULTS

Using combinations of JVN image displays, JVN images were shown to match diagnosed level of diabetic retinopathy as determined from record notes and/or ETDRS seven-standard field stereoscopic 35-mm retinal fundus photography. Viewing images with various combinations of JVN image displays delineates possible sources of artifacts in JVN images. Areas to guide future image capture and image reading are identified.

CONCLUSIONS

The JVN image capture system and reading of images by certified readers should allow appropriate photodiagnostic information to support the JVN, the diabetes mellitus disease management telemedicine initiative of the Joslin Diabetes Center. A rigid, full-scale, masked study to compare the Joslin Vision Network to seven-standard field stereoscopic 35-mm retinal fundus photography should be pursued to validate the image-gathering and image-reading strategy to support the Joslin Vision Network.

Cluster analysis of self-awareness levels in adults with traumatic brain injury and relationshipto outcome

The purpose of this study was to investigate the relationship between self-awareness, emotional distress, motivation, and outcome in adults with severe traumatic brain injury. A sample of 55 patients were selected from 120 consecutive patients with severe traumatic brain injury admitted to the rehabilitation unit of a large metropolitan public hospital. Subjects received multidisciplinary inpatient rehabilitation and different types of outpatient rehabilitation and community-based services according to availability and need. Measures used in the cluster analysis were the Patient Competency Rating Scale, Self-Awareness of Deficits Interview, Head Injury Behavior Scale, Change Assessment Questionnaire, the Beck Depression Inventory, and Beck Anxiety Inventory; outcome measures were the Disability Rating Scale, Community Integration Questionnaire, and Sickness Impact Profile. A three-cluster solution was selected, with groups labeled as high self-awareness (n = 23), low self-awareness (n = 23), and good recovery (n = 8). The high self-awareness cluster had significantly higher levels of self-awareness, motivation, and emotional distress than the low self-awareness cluster but did not differ significantly in outcome. Self-awareness after brain injury is associated with greater motivation to change behavior and higher levels of depression and anxiety; however, it was not clear that this heightened motivation actually led to any improvement in outcome. Rehabilitation timing and approach may need to be tailored to match the individual's level of self-awareness, motivation, and emotional distress.

Seronegative myasthenia gravis and human immunodeficiency virus infection: response to intravenous gamma globulin and prednisone

BACKGROUND

There are only rare reports of myasthenia gravis complicating human immunodeficiency virus infection. The role of immunomodulatory therapy is unknown.

METHODS

Case report and literature review.

RESULTS

The diagnosis of human immunodeficiency virus infection followed that of myasthenia gravis in a 35-year-old man. Clinical and electrophysiological features were diagnostic of generalized myasthenia gravis but two edrophonium chloride tests and acetylcholine receptor antibodies were negative. Prednisone therapy and intravenous gamma globulin were associated with rapid clinical recovery.

CONCLUSIONS

Prednisone therapy and intravenous gamma globulin may be helpful in patients with generalized myasthenia gravis complicating HIV infection.

A randomized trial comparing three methods of bowel preparation for flexible sigmoidoscopy

OBJECTIVE

The aim of this study was to assess the optimum method of bowel preparation for flexible sigmoidoscopy.

METHODS

A total of 164 adults undergoing flexible sigmoidoscopy at an ambulatory clinic were randomized to receive one of three preparations: a single hyperphosphate enema 1 h before the procedure; a hyperphosphate enema given 1 and 2 h before the procedure; or a hyperphosphate enema administered 1 and 2 h before the procedure, preceded by a 296 ml bottle of magnesium citrate taken p.o. the night before. Patients completed surveys on preparation and procedure comfort and satisfaction. The performing endoscopist assessed preparation quality, procedure duration, and depth of sigmoidoscope insertion.

RESULTS

All three preparations were equally well tolerated with slightly more diarrhea reported among patients receiving magnesium citrate (p = 0.007). The addition of magnesium citrate resulted in more procedures rated by the endoscopist as excellent or good (RR 1.5, 95% CI: 1.3-1.9), deeper sigmoidoscope insertion (56 vs 51 cm, p = 0.0036), fewer procedures requiring repeat preparation (RR: 0.21, 95% CI: 0.04-0.98) and more procedures rated by patients as discomfort free (RR: 2.2, 95% CI: 1.39-3.60). Excellent and good preparations were associated with shorter procedure duration (19 vs 14 min, p = 0.008) and greater depth of insertion (56 vs 50 cm, p = 0.003). Fewer diverticuli were noted with a single enema than the two enema preparation (p = 0.006) with the remaining outcomes equal between these two groups.

CONCLUSION

The addition of bottle of magnesium citrate to a 2-hyperphosphate enema preparation is well tolerated and improves bowel preparation for flexible sigmoidoscopy.

The concept of well-being in a rural setting: understanding health and illness

Attitudes to health and illness may differ between rural and urban dwellers. Issues that may relate to the provision of health services to rural dwellers are raised for consideration. The response of urban dwellers to illness or disability has often been linked to discomfort caused by pain or cosmetic attractiveness, while for rural dwellers the response to illness or disability is often related to the degree to which the illness or disability affects productivity. Often the rural resident will postpone seeking medical or associated services until it is economically or socially convenient. The notion of exposing their private lives to strangers or acquaintances from the local based services or to undertake the journey to distant services where the cultural or behavioural differences could be misunderstood, may impact on rural dwellers' well-being. Health service providers in rural areas need to understand such differences and difficulties when offering services.

The reliability and validity of a measure of perceived functional capacity for work in chronic back pain

Psychosocial factors, including perceived disability and self-efficacy, are important determinants of outcome for individuals with chronic back pain. Consequently, there is a need for an evaluation and consideration of such factors in occupational rehabilitation. This study evaluated the reliability and validity of a tool, the Spinal Function Sort, as a measure of perceived capacity for work-related tasks with 42 rehabilitation clients with chronic back pain. Results provided support for the internal consistency (Cronbach's alpha of 0.97), test-rest reliability (ICC of 0.89) and construct validity of the Spinal Function Sort as a measure of perceived capacity for work-related tasks in persons with chronic back pain. Measures of similar constructs were significantly correlated with the Spinal Function Sort and were highly predictive of the Spinal Function Sort on multiple regression. Relationships between perceived work capacity and pain intensity and gender are discussed. The need for the consideration of perceived capacity in the evaluation and rehabilitation of persons with chronic back pain is highlighted.

Self-awareness of deficits in adults with traumatic brain injury: how best to measure?

Some method of assessing self-awareness of deficits in patients with traumatic brain injury (TBI) is required to increase our understanding of the phenomenon, and to then evaluate strategies for clinical intervention with patients who lack such self-awareness. Options for the assessment of self-awareness of deficits following TBI are reviewed. The most commonly used method is comparison of patients' self-ratings on questionnaires of functional abilities with ratings by relatives or staff on the same questionnaires. An additional method of assessment, an interviewer-rated semi-structured interview is proposed (the Self-Awareness of Deficits Interview), and some preliminary inter-rater reliability data are presented. However, quantitative methods of evaluating self-awareness have shortcomings, and qualitative research may be more appropriate in some circumstances. An approach which makes use of multiple measures to evaluate self-awareness of deficits is recommended.