Development of a highly sensitive magneto-enzyme lateral flow immunoassay for dengue NS1 detection.

BACKGROUND: Dengue infection represents a global health issue of growing importance. Dengue non-structural protein 1 (NS1) plays a central role in the early detection of the disease. The most common method for NS1 detection is testing by lateral flow immunoassays (LFIAs) with varying sensitivity. In this study, we present a highly sensitive magneto-enzyme LFIA for prompt diagnosis of dengue. METHODS: We have demonstrated the development of a magneto-enzyme LFIA combining super-paramagnetic nanoparticles as labels and Biotin-Streptavidin signal amplification strategy to detect dengue NS1. Factors affecting the test performance including antibody pair, super-paramagnetic nanoparticle size, nitrocellulose membrane type, amounts of detection and capture antibodies, and amounts of Streptavidin-polyHRP were optimized. Analytical sensitivity and cross-reactivity were determined. Clinical performance of the novel assay was evaluated using a panel of 120 clinical sera. RESULTS: This newly developed assay could detect NS1 of all four serotypes of dengue virus (DENV). The limit of detection (LOD) was found to be as low as 0.25 ng ml-1 for DENV-1 and DENV-3, 0.1 ng ml-1 for DENV-2, and 1.0 ng ml-1 for DENV-4. The LOD for DENV-2 was a 50-fold improvement over the best values previously reported. There was an absence of cross-reactivity with Zika NS1, Hepatitis B virus, Hepatitis C virus, and Japanese encephalitis virus. The sensitivity and specificity of the novel assay were 100% when tested on clinical samples. CONCLUSIONS: We have successfully developed a magneto-enzyme LFIA, allowing rapid and highly sensitive detection of dengue NS1, which is essential for proper management of patients infected with DENV.

Sensitivity to change of the Quebec Back Pain Disability Scale and the Dallas Pain Questionnaire.

OBJECTIVE: To study and compare the sensitivities to change of the French versions of the Quebec Back Pain Disability Scale (QBPDS) and the Dallas Pain Questionnaire (DPQ). METHOD: A retrospective study of the medical records of 30 chronic low back pain (LBP) outpatients undergoing a 4-week functional training program in a physical medicine and rehabilitation unit. Physical data (a visual analogue pain scale, the Schöber index, Sorensen and Shirado tests and the finger-to-floor distance) and functional status (QBPDS and DPQ scores) were measured at D0 and D25. Sensitivity to change was assessed in terms of the standardized response mean (SRM) and the effect size (ES). RESULTS: With the exception of the DPQ's "social interest" domain, all QBPDS and DPQ scores improved significantly over the course of the rehabilitation programme. Sensitivity to change was high for the QBPDS (SRM=0.80; ES=0.62) but only moderate for the DPQ (SRM=0.59; ES=0.61). DISCUSSION-CONCLUSION: Our results show that the QBPDS was more sensitive to clinical change than the DPQ in a sample of chronic LBP sufferers. It would be interesting to assess this sensitivity in a population of acute LBP patients and to evaluate the long-term effects of a functional rehabilitation program on the DPQ's "social interest" domain.

Oncology and physical medicine and rehabilitation.

INTRODUCTION: Cancer patients are living longer with deficiencies and functional impairments requiring often typically a care in physical medicine and rehabilitation (PMR). OBJECTIVE: To examine the care of cancer patients in PMR. METHOD: Investigation made with a questionnaire diffused from the e-mail listing of the Société Française de Médecine Physique et de Réadaptation. RESULTS: Sixty-seven answers received. Fifty-seven centers take care of cancer patients. On average, 4% of cancer patients are hospitalised in PMR. Spinal cord injuries and hemiplegias are the most common impairments. Forty-two percent of the PMR units take the patients in all the stages of cancer treatment. Working relationships between PMR and oncology units are formalized only eight times out of 52. In case of health degradation, relationships with a palliative care unit are frequent but not generalized. Eighty-five percent of the centers think that PMR is not enough developed in oncology. CONCLUSIONS: In spite of its limited character, this investigation shows that the PMR units take these patients. Situations where PMR has an important role in the follow-up of cancer patients are multiple and publications have showed its interest, especially on the limitations of activities. It is important to make better known the interest of PMR in oncology units but also to develop specific care within PMR units.

Dantrolene and pleural effusion: case report and review of literature.

STUDY DESIGN: Single-subject case (a quadriplegic female, 56 years). OBJECTIVES: To describe a new case of eosinophilic pleural effusion induced by dantrolene chronic administration. SETTING: Physical medicine and rehabilitation unit in a teaching hospital, France. METHODS: Diagnosis of an eosinophilic pleural effusion induced by dantrolene without any respiratory symptoms, except a decrease of breath sounds on the right lung base. RESULTS: Chest radiograph revealed a right-sided pleural effusion, and blood cell count a significant peripheral eosinophilia. Thoracenthesis contained 85% of eosinophils. The other explorations eliminated other causes of pleural effusion. The diagnosis of drug-induced effusion was almost sure and led us to discontinue the dantrolene. After 3 months, she had completely recovered. These characteristics, similar to the eight other cases described in the literature, are essential for the diagnosis of pleural effusion induced by dantrolene. CONCLUSION: Dantrolene, a long-acting skeletal muscle relaxant, is well known to induce liver side effects but it can also induce pleural pericarditis. The pathogenesis is still not clearly identified, but similarities of chemical structures of dantrolene and nitrofurantoine make us think that it could be the same mechanism. The association between dantrolene and nitrofurantoine may have contributed to the expression of the pleural effusion.

[Functional assessment scales and lower limb amputation]. / Echelles d'évaluation fonctionnelle et amputation du membre inférieur.

INTRODUCTION: This paper is a review of the literature on assessment tools in lower limb amputees. MATERIAL AND METHODS: The authors have research on Medline(R) data base the different tools with keys words "lower limb amputee or amputation, functional evaluation or outcome assessment tools, activity of daily living", and have completed the research with the references of papers. RESULTS: A comprehensive approach of the consequences of an amputation and of the outcome of prosthetic care should include an evaluation of gait, use of the prosthesis in activities of daily life, acceptability and satisfaction with the device. DISCUSSION: Functional assessment tools that are validated are recent, and most of them were developed in English. They take into account the use and the acceptance of the device, but there is no study using them for an important sample population. CONCLUSION: It is now necessary to translate the recent tools into French, and to confirm their validity and sensitivity to change.