Simultaneous estimation of muscle fibre conduction velocity and muscle fibre orientation using 2D multichannel surface electromyogram

The paper presents a new approach for simultaneous estimation of muscle fibre conduction velocity (MFCV) and muscle fibre orientation (MFO) for motor units (MUs) in two-dimensional (2D) multichannel surface electromyography recordings. This is an important tool for detecting changes and abnormalities in muscle function and structure. In addition, simultaneous estimation of MFO and MFCV avoids the necessity of manual electrode alignment. The proposed method detected propagating MU action potentials (MUAPs) in a running time window as moving components in amplitude maps. Thereafter, estimations were obtained by fitting a three-dimensional function to these maps. The performance was evaluated using synthetic MU signals at 10 dB SNR and authentic biceps brachii measurements. Results demonstrated MFCV and MFO estimates with standard deviations of less than 0.05 m s⁻¹ and 1° for simulated signals, and less than 0.2 m s⁻¹ and 4° for experimental data. However, standard deviations as low as 0.12 m s⁻¹ and 1.6° from real signals were demonstrated. It was concluded that the method performs as well as, or better than, linear array multichannel methods when individual propagating MUAPs can be identified, even if electrodes are not aligned with fibre direction.     

Involvement of the NMDA receptor, NO-cyclic GMP and nuclear factor K-beta in an animal model of repeated trauma

Post-traumatic stress disorder (PTSD) may be associated with shrinkage of the hippocampus, with glutamate release causally related to these events. Recent animal studies strongly implicate activation of the nitric oxide (NO)-cascade in anxiety and stress. Using an animal model of repeated trauma, the effect of stress was investigated on the hippocampal NO-cGMP signalling pathway, specifically the release of nitrogen oxides (NOx) and its modulation by NMDA receptor-, NO-, cGMP- and nuclear factor K-beta (NFK-beta)-selective drugs. Immediately after stress, rats received the glutamate NMDA receptor antagonist, memantine (MEM; 5 mg/kg i.p./d), the NO synthase inhibitor, 7-nitroindazole sodium salt (7-NINA; 20 mg/kg i.p./d), the cGMP-specific PDE inhibitor, sildenafil (SIL; 10 mg/kg i.p./d) or the NFkappa-beta antagonist, pyrollidine dithiocarbamate (PDTC; 70 mg/kg i.p./d), for 7 days. Stress significantly increased hippocampal NOx on day 7 post-stress, which was blocked by either 7-NINA or PDTC, while MEM was without effect. SIL, however, significantly augmented stress-induced NOx accumulation. Increased cGMP therefore acts as a protagonist in driving stress-related events, while both nNOS (neuronal NOS) and iNOS (inducible/immunological NOS) may represent a therapeutic target in preventing the effects of severe stress. The value of NMDA receptor antagonism, however, appears limited in this model.     

Effectiveness of resistance training in combination with botulinum toxin-A on hand and arm use in children with cerebral palsy: A pre-post intervention study

ABSTRACT: BACKGROUND: The aim of this study was to investigate effects of additional strength training after use of Botulinum Toxin-A (BoNT-A) in the upper limbs of children with cerebral palsy (CP). METHODS: Ten children with CP (range 9 - 17 years, Manual Ability Classification System II) with unilaterally affected upper limbs were assigned to two intervention groups. One group received BoNT-A treatment (group B), the other BoNT-A plus 8 weeks strength training (group BT). Hand activity was measured with Melbourne assessment of unilateral upper limb function (Melbourne) and Assisting Hand Assessment (AHA). Measures of muscle strength, muscle tone, and active range of motion were used to assess neuromuscular body function. Measurements were performed before and two and five months after intervention start. Change scores and differences between the groups in change scores were statistically tested in SPSS version 18, using Mann-Whitney U test and Wilcoxon Signed Rank test, respectively. RESULTS: Both groups had very small improvements in AHA and Melbourne two months after BoNT-A injections, without differences between groups. There were significant, or close to significant, short-term treatment effects in favour of group BT for muscle strength in injected (elbow flexion strength, p=0.08) and non-injected muscles (elbow extension and supination strength, both p=0.05), without concomitant increases in muscle tone. Active supination range improved in both groups but more so in group BT (p= 0.09). There were no differences between the groups three months after training ended. CONCLUSIONS: Strength training strengthens non-injected muscles temporarily and may reduce short term strength loss that results from BoNT-A injections without increasing muscle tone. Moreover, additional strength training may increase active range of motion to a larger extent than BoNT-A alone. None of the improvements in neuromuscular body functions further improved hand activity. Larger clinical trials are needed to further investigate whether strength training can counteract strength loss caused by BoNT-A, whether the combination of BoNT-A and strength training is superior to BoNT-A or strength training alone in improving active range of motion, and whether more task-related strength training is a more effective approach to improve hand activity.     

Swallowing abnormalities in HIV infected children: an important cause of morbidity

Background

Evaluation of palpable neck masses may be a diagnostic problem in pediatric patients, with differential diagnosis including congenital, inflammatory, tumoral and traumatic lesions. Ultrasonography is usually a satisfactory method to make a correct pre-operative evaluation of neck masses, although diagnosis is often challenging for the surgeon and the radiologist and sometimes only possible after a histopathological examination of the resected lesion.

Case presentation

We report an 8-month-old patient with a cervical, anterior midline mass. Ultrasonographic images showed features suggesting a partly cystic lesion, with a preoperative suspect of thyroglossal duct cyst. Histological examination, performed after surgical removal of the mass, led to a diagnosis of lymph node angiomyomatous hamartoma (AH).

Conclusions

AH, a rarely occurring benign lymph node lesion, has been reported in the neck lateral region only twice. This case, presenting as a palpable neck midline mass, is the first reported case occurring in infancy. Although rare, AH should be included in the differential diagnosis of head and neck masses.     

Research perspectives in the etiology of congenital anorectal malformations using data of the International Consortium on Anorectal Malformations: evidence for risk factors across different populations

Purpose

The recently established International Consortium on Anorectal Malformations aims to identify genetic and environmental risk factors in the etiology of syndromic and nonsyndromic anorectal malformations (ARM) by promoting collaboration through data sharing and combined research activities.

Methods

The consortium attempts to recruit at least 1,000 ARM cases. DNA samples are collected from case–parent triads to identify genetic factors involved in ARM. Several genetic techniques will be applied, including SNP arrays, gene and whole exome sequencing, and a genome-wide association study. Questionnaires inquiring about circumstances before and during pregnancy will be used to obtain environmental risk factor data.

Results

Currently, 701 ARM cases have been recruited throughout Europe. Clinical data are available from all cases, and DNA samples and questionnaire data mainly from the Dutch and German cases. Preliminary analyses on environmental risk factors in the Dutch and German cohort found associations between ARM and family history of ARM, fever during first trimester of pregnancy and maternal job exposure to cleaning agents and solvents.

Conclusion

First results show that both genetic and environmental factors may contribute to the multifactorial etiology of ARM. The International Consortium on Anorectal Malformations will provide possibilities to study and detect important genes and environmental risk factors for ARM, ultimately resulting in better genetic counseling, improved therapies, and primary prevention.     

Taking the eagle's view: using Watson's conceptual model to investigate the extraordinary and transformative experiences of nurse healers

Watson's conceptual model of a caring-healing transpersonal understanding of nursing was used to underpin a hermeneutic phenomenological study of the extraordinary and transformational experiences of nurse healers. The 5 essential themes uncovered from the analysis of interviews with 11 nurse healers--Belonging & Connecting, Opening to Spirit, Summoning, Wounding & Healing Journey, and Living as a Healer--are set out, along with the overarching theme "Walking Two Worlds." Foundational understandings of Watson's model as they relate to the findings, and theoretical aspects, are discussed, and potential contributions of this study to the ongoing evolution of Watson's conceptual model are articulated.     

Community mental health nurses speak out: the critical relationship between emotional wellbeing and satisfying professional practice

The article reports on selected findings of a research study concerning emotional wellbeing and professional nursing practice (Rose 2002). It highlights the relationship between community mental health nurses' and emotional wellbeing, and their capacity to provide satisfying professional nursing practice (Rose 2002). The notion of emotional wellbeing, factors that impacted upon the participants' emotional wellbeing, and the relationship of emotional wellbeing to professional practice were revealed in the study. These findings were based on a qualitative critical feminist research inquiry and specifically, interviews with five women community mental health nurses in Australia. Whilst complex, emotional wellbeing was found to be both implicitly and explicitly linked to the participants intertwined personal and professional experiences. Four key components were identified: the nebulous notion; the stress relationship; the mind, body, spirit connection; and, inner sense of balance. In terms of emotional wellbeing and professional practice, three themes were revealed. These were: being able to speak out (or not); being autonomous (or not) and being satisfied (or not). The authors argue that the emotional wellbeing of nurses working in community mental health settings is critical to satisfying professional practice. Furthermore nursing work involves emotional work which impacts on one's emotional wellbeing and emotional wellbeing is integrally linked to professional practice. It is recommended that health organisations must be pro-active in addressing the emotional needs of nurses to ensure the delivery of health care that is aligned to professional practice. This approach will ensure nurses will feel more recognised and validated in terms of their nursing practice.