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Intensive pain rehabilitation programs for children with chronic pain are effective for many patients. However, characteristics associated with treatment response have not been well documented. In this article we report trajectories of pain and functional impairment in patients with chronic pain up to 1 year after intensive pain rehabilitation and examine baseline factors associated with treatment response. Patients (n?=?253) with chronic pain and functional disability were assessed at 5 time points (admission, discharge, 1-month, 4-month, and 12-month follow-ups). Individual trajectories were empirically grouped using SAS PROC TRAJ. For functional disability, 2 groups emerged: treatment responders (88%) and nonresponders (12%). Using a binomial logistic regression model to predict disability trajectory group, no baseline variables were significant predictors for the disability trajectory group. For pain, 3 groups emerged: early treatment responders (35%), late treatment responders (38%), and nonresponders (27%). Using multinomial regression analyses to predict pain trajectory group, older age, higher pain scores, fewer social difficulties, higher anxiety levels, and lower readiness to change were characteristics that distinguished nonresponders from responders; no significant predictors distinguished the late responders from the early responders. These results provide key information on the baseline factors that influence intensive pain rehabilitation outcomes, including risk factors that predict treatment nonresponse. Our findings have implications for developing more targeted treatment interventions.

Perspective

Deriving groups of individuals with differing treatment response trajectories stimulates new thinking regarding potential mechanisms that may be driving these outcomes.  相似文献   
995.
Changes in excitability of the sensorimotor cortex have been demonstrated in clinical musculoskeletal pain, although the timing is unknown. Eccentric exercise provokes delayed-onset muscle soreness providing a model to study the temporal profile of sensorimotor cortical plasticity during progressively developing muscle soreness. Twelve healthy participants performed eccentric exercise of the wrist extensors. Likert pain scores, pressure pain thresholds at the extensor carpi radialis (ECR) muscle, somatosensory evoked potentials from electrical stimulation of the radial nerve, maximal wrist extension force, and ECR motor evoked potentials to transcranial magnetic stimulation were recorded before (baseline) and at 2 hours (2-h post), 2 days (day 2), and 6 days (day 6) after exercise. Compared with baseline, 1) the Likert pain score was increased at 2-h post and increased further at day 2 (P < .01); 2) the ECR pressure pain thresholds were decreased at day 2 (P < .001); 3) the P45 amplitude of the somatosensory evoked potential from central-parietal recording sites was increased at day 2 (P < .001); 4) maximal wrist extension force was reduced 2-h post and at day 2 (P < .002); and 5) the cortical area from which ECR motor evoked potentials could be elicited was reduced at 2-h post and at day 2 (P < .03). A decrease in the ECR pressure pain thresholds was correlated (P < .027) with an increase in the P45 amplitude at a centroparietal recording site.

Perspective

These novel data demonstrate that the somatosensory cortical excitability may be affected by muscle soreness developing over days in parallel with a deficit in the motor system. Cortical neuroplasticity may thus develop in the subacute phase and be relevant for understanding neural adaptation in the transition from acute to persistent pain.  相似文献   
996.

Purpose of Review

Pituitary tumors account for approximately 17% of all intracranial neoplasms, with the majority being pituitary adenomas. Often, these are found incidentally during a workup for headache; however, the relationship between symptom and pathology remains unclear. The purpose of this article is to review the most recent literature on the epidemiology, pathophysiology, and management of headaches in patients with pituitary tumors.

Recent Findings

The current literature is limited, with few prospective trials focusing on this question. With the exception of pituitary apoplexy, the relationship between headaches and pituitary masses remains unclear. Intervention does not always improve headache and can lead to development of new headache syndromes.

Summary

Further research is needed to better elucidate the relationship between pituitary tumors and headaches. Headache alone is rarely an indication for surgical management of a pituitary adenoma.
  相似文献   
997.

Purpose

To evaluate whether ultrasmall superparamagnetic iron oxide nanoparticle (USPIO)-enhanced magnetic resonance imaging (MRI) can detect allograft rejection in pediatric kidney transplant patients.

Procedures

The USPIO ferumoxytol has a long blood half-life and is phagocytosed by macrophages. In an IRB-approved single-center prospective clinical trial, 26 pediatric patients and adolescents (age 10–26 years) with acute allograft rejection (n = 5), non-rejecting allografts (n = 13), and normal native kidneys (n = 8) underwent multi-echo T2* fast spoiled gradient-echo (FSPGR) MRI after intravenous injection (p.i.) of 5 mg Fe/kg ferumoxytol. T2* relaxation times at 4 h p.i. (perfusion phase) and more than 20 h p.i. (macrophage phase) were compared with biopsy results. The presence of rejection was assessed using the Banff criteria, and the prevalence of macrophages on CD163 immunostains was determined based on a semi-quantitative scoring system. MRI and histology data were compared among patient groups using t tests, analysis of variance, and regression analyses with a significance threshold of p < 0.05.

Results

At 4 h p.i., mean T2* values were 6.6 ± 1.5 ms for native kidneys and 3.9 ms for one allograft undergoing acute immune rejection. Surprisingly, at 20–24 h p.i., one rejecting allograft showed significantly prolonged T2* relaxation times (37.0 ms) compared to native kidneys (6.3 ± 1.7 ms) and non-rejecting allografts (7.6 ± 0.1 ms). Likewise, three additional rejecting allografts showed significantly prolonged T2* relaxation times compared to non-rejecting allografts at later post-contrast time points, 25–97 h p.i. (p = 0.008). Histological analysis revealed edema and compressed microvessels in biopsies of rejecting allografts. Allografts with and without rejection showed insignificant differences in macrophage content on histopathology (p = 0.44).

Conclusion

After ferumoxytol administration, renal allografts undergoing acute rejection show prolonged T2* values compared to non-rejecting allografts. Since histology revealed no significant differences in macrophage content, the increasing T2* value is likely due to the combined effect of reduced perfusion and increased edema in rejecting allografts.
  相似文献   
998.
As the cases of heart failure continue to rise, more ventricular assist devices are likely to be implanted. Providers in a variety of care environments are more likely to see patients with ventricular assist devices because they are living longer; therefore, it is necessary for providers to understand the unique care and complications related to these devices, such as thrombosis, stroke, bleeding, right-sided heart failure, ventricular dysrhythmias, and infection. The current literature regarding the complications and management of patients with these devices was reviewed and summarized, with a focus on HeartWare (HeartWare International Inc, Framingham, MA) and HeartMate II (Thoratec Corp, Pleasanton, CA).  相似文献   
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1000.
Heart failure (HF) is an increasingly prevalent long‐term condition that affects around 900,000 people in the United Kingdom (National Institute for Health and Clinical Excellence). The study examined how HF services in the English National Health Service (NHS) were changing, focusing particularly on the primary/secondary care interface. The maintenance of continuity in care in the face of increasing demand and financial pressures on health and social care was a key concern. Semi‐structured interviews were conducted with 22 members of staff working in HF services in three NHS acute Trusts in the West Midlands of England. Interviews were conducted between April and December 2011 with purposively selected participants and data were analysed using the Framework Method. Four main themes emerged from the analysis: service context, capacity, the primary/secondary interface and communication across boundaries. Barriers to, and facilitators of, continuity of care for patients with HF were identified within these themes. The findings provide insights into the structure, management and work of HF services in the acute and community settings. They highlight how local systems for the management of HF patients are developing in ways which are not necessarily consistent with national policy.  相似文献   
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