Methylphenidate in children with hyperactivity: review and cost-utility analysis

OBJECTIVE

To evaluate the effectiveness and cost effectiveness of methylphenidate in the treatment of children with hyperkinetic disorder as defined using ICD-10 criteria.

DESIGN

Comprehensive literature review and cost utility analysis comparing methylphenidate treatment with placebo. Costs and effects were estimated from a NHS perspective according to the methodology developed by the previous South and West Development and Evaluation Committee. The number of Quality Adjusted Life Years (QALYs) gained was estimated by using the Index of Health Related Quality of Life to model treatment effects.

RESULTS

Evidence from good and medium quality randomized controlled trials shows benefits of methylphenidate over weeks and months respectively. Evidence beyond 6 months is poorer and it is uncertain whether effects of methylphenidate persist into adolescence and adulthood. Methylphenidate is of reasonable cost-effectiveness when considering short- and medium- term benefits with an estimated cost per QALY of 7 pounds 400 to 9 pounds 200 at 1997 prices.

CONCLUSIONS

Short-term treatment of hyperkinetic children with methylphenidate is effective and cost effective.

Risk of secondary meningococcal disease in health-care workers

Guidelines on chemoprophylaxis vary between countries and reflect uncertainty about the risk of meningococcal disease in healthcare workers. In a retrospective survey of risk in healthcare workers in England and Wales, three pairs of primary cases and health-care workers with secondary infections were identified between 1982 and 1996. Secondary infections were probably caused by exposure to primary cases' respiratory droplets around the time of admission. We estimated an attack rate of 0.8 per 100000 health-care workers at risk, a risk 25 times that in the general population (p=0.0003). The excess risk is small and inappropriate use of prophylactic antibiotics should be avoided.

Mechanical comparison of a distal femoral side plate and a retrograde intramedullary nail

OBJECTIVE

To compare quantitatively the axial and torsional stiffness of a retrograde intramedullary nail and a fixed angle screw side plate in treating a supracondylar femur fracture in osteopenic femora. To determine the modes of failure of an intramedullary nail and a side plate under axial loading.

DESIGN

Matched pair cadaveric study.

SETTING

Orthopaedic biomechanics laboratory.

PATIENTS AND OTHER PARTICIPANTS

Eleven matched pairs of preserved human femora were selected. The cadaveric specimens were harvested from relatively elderly donors with an average age of 75.6 years, which represents the principal population at risk for poor fracture fixation.

INTERVENTION

The eleven matched pairs were osteotomized to simulate segmental structural defects in the supracondylar region. One femur of each matched pair was fixed with an intramedullary nail, and the contralateral femur was fixed with a side plate.

MAIN OUTCOME MEASURES

Axial and torsional stiffness values. Axial modes of failure.

RESULTS

The intramedullary nail axial stiffness was 14 percent (p = 0.04) less and torsional stiffness was 17 percent (p = 0.05) less than that provided by the side plate. The axial failure of the intramedullary nail occurred distally, allowing the hardware to protrude into the articular space. The side plate also failed distally by displacing the condylar screw into a varus angulation.

CONCLUSION

The mechanical advantages favor the use of the side plate if fixation stiffness is essential. The axial mode of failure occurs distally for both fixation devices.

Bizarre parosteal osteochondromatous proliferation of bone (BPOP): an unusual foot mass in a child

This report describes an unusual case of bizarre parosteal osteochondromatous proliferation of bone (BPOP) which developed in the foot of an eight year-old child. Also described as Nora's lesion, BPOP is a rare benign bone tumor found most commonly in the hands and feet with a radiographic appearance occasionally confused with malignancy. Resembling osteochondromas at first glance, these lesions have a distinct radiographic and histologic appearance that permits differentiation from other benign lesions or low-grade malignant tumors. Treatment of BPOP consists of simple excision, although there is high rate of recurrence. Despite this high recurrence rate, there have been no reported metastases and local excision is still recommended.

Radiographic Evaluation of Children and Adolescents with a Spinal Deformity

Accurate and reproducible measurement of radiographs of children and adolescents with spinal deformities by radiologists is important. It provides useful information for treating physicians. Standing posteroanterior (PA) and lateral radiographs of the entire spine are the preferred views. Common radiographic measurements include the Cobb angle for curve magnitude, the center sacral line for trunk shift, and the Risser sign for maturity. A vocabulary of standard spinal deformity terminology is presented to be utilized on radiographic reports to improve communication. Correctly measuring spinal deformity and determining skeletal maturity enables the treating physician to evaluate the status of their patients' deformity, determine if treatment is necessary, and assess the stability of the spine during orthotic treatment and after surgery.

Meningococcal disease at the University of Southampton: outbreak investigation

In October 1997, an outbreak of meningococcal disease occurred at the University of Southampton. All six cases were first year students living in halls of residence. Microbiological characterization of case and carrier strains, case interviews, and a meningococcal carriage prevalence survey were used to investigate the outbreak. Five cases were due to serogroup C strains, one case was unconfirmed. Serotyping did not distinguish between the strains but gene sequencing permitted identification of two distinct strains in the outbreak. Although none of the cases was known to each other, three had attended the same nightclub one evening 3-4 days before illness. Meningococcal carriage rates in undergraduates were within the range expected (147/587, 25%), but no carriers of outbreak strains were identified in this sample. The findings suggest that in communities with a high degree of social interaction, the introduction of highly virulent meningococcal strains may result in enhanced transmission with clustering of cases.

Integrin-mediated activation of focal adhesion kinase is independent of focal adhesion formation or integrin activation. Studies with activated and inhibitory beta3 cytoplasmic domain mutants

Integrin alphaIIbbeta3 functions as the fibrinogen receptor on platelets and mediates platelet aggregation and clot retraction. Among the events that occur during either "inside-out" or "outside-in" signaling through alphaIIbbeta3 is the phosphorylation of focal adhesion kinase (pp125(FAK)) and the association of pp125(FAK) with cytoskeletal components. To examine the role of pp125(FAK) in these integrin-mediated events, pp125(FAK) phosphorylation and association with the cytoskeleton was determined in cells expressing two mutant forms of alphaIIbbeta3: alphaIIbbeta3(D723A/E726A), a constitutively active integrin in which the putative binding site for pp125(FAK) is altered, and alphaIIbbeta3(F727A/K729E/F730A), in which the putative binding site for alpha-actinin is altered. Both mutants were expressed on the cell surface and were able to bind ligand, either spontaneously or upon activation. Whereas cells expressing alphaIIbbeta3(D723A/E726A) were able to form focal adhesions and stress fibers upon adherence to fibrinogen, cells expressing alphaIIbbeta3(F727A/K729E/F730A) adhere to fibrinogen, but had reduced focal adhesions and stress fibers. pp125(FAK) is recruited to focal adhesions in adherent cells expressing alphaIIbbeta3(D723A/E726A) and is phosphorylated in adherent cells or in cells in suspension in the presence of fibrinogen. In adherent cells expressing alphaIIbbeta3(F727A/K729E/F730A), pp125(FAK) was phosphorylated despite reduced formation of focal adhesions and stress fibers. We conclude that activation of pp125(FAK) can be dissociated from two important events in integrin signaling, the assembly of focal adhesions in adherent cells and integrin activation following ligand occupation.

Strategies for improving job security: decreasing anxiety from restructuring

Nurses are worried about the future of nursing and, more specifically, about the future of their own job. This author who is experienced in working with nurses on job security issues and clarifying layoff policies suggests strategies that can help improve nurses' feelings of job security even during this time of restructuring.

Clinical practice guidelines: weapons for patients, or shields for MDs?

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Ottawa's "Operation Meningo": "when the data are insufficient, you go with judgement"

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Ottawa's meningococcal outbreak provided a lesson in professional judgement and science

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Taking care of business: MDs in search of management skills turning to MBA courses

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With new Ottawa centre, acute care and health promotion share same address

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Issues handled by CMA Council on Health Care multiplying

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In vitro studies on the action of CS-045, a new antidiabetic agent

The mechanism of action of CS-045, a new orally active antidiabetic agent, was studied in vitro using cultured hepatoma cells (Hep G2) and muscle cells (BC3H-1). Treatment of both types of cultured cells with varying doses of CS-045 did not significantly alter insulin receptor binding. Basal and insulin-stimulated glucose transport in BC3H-1 cells was also unaltered by the drug. In contrast, CS-045 increased glycogen synthase I activity in both cell types. This effect was maximal after 24 hours and in Hep G2 cells was associated with a threefold increase in the apparent affinity of the enzyme for glucose-6-phosphate. Gluconeogenesis from lactate in Hep G2 cells was greatly reduced by CS-045 treatment. We conclude that CS-045 may act directly on muscle and liver cells to increase glucose utilization. It is also effective in reducing glucose production. These multiple effects may account in part for the ability of CS-045 to reduce blood sugar levels in vivo.

New department means ethics and law have moved centre stage at CMA

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Canada's native MDs: small in number, big on helping their community

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