Motor unit action potential amplitudes and firing rates during repetitive muscle actions of the first dorsal interosseous in children and adults

Abstract

Purpose

Previous research has indicated greater muscle activation is needed for children (CH) to match relative intensity submaximal contractions in comparison with adults (AD). However, no study has compared motor unit (MU) firing and recruitment patterns between children and adults. Therefore, MU action potential amplitudes (MUAP_AMP) and firing rates were examined during two repetitive submaximal contractions of the first dorsal interosseous in children and adults.

Methods

Twenty-two children (age 9.0 ± 0.8 years) and 13 adults (age 22.9 ± 4.8 years) completed three maximum voluntary contractions (MVC) and two repetitive isometric contractions at 30% MVC for 40 s. Surface electromyography (EMG) was recorded and decomposed into action potential trains. MUAP_AMPS, recruitment thresholds (RTs), and mean firing rates (MFRs) were calculated, and EMG amplitude was normalized (N-EMG) to MVC. For each subject and repetition, linear MFR vs. RT and exponential MUAP_AMP vs. RT and MFR vs. MUAP_AMP relationships were calculated.

Results

N-EMG (P = 0.001, CH = 56.5 ± 31.7%, AD = 30.3 ± 9.1%), MFRs regardless of RT, according to greater y-intercepts of the MFR vs. RT relationships [P = 0.013, CH = 31.1 ± 5.1 pulses per second (pps), AD = 25.9 ± 4.3 pps] and MFRs of MUs with smaller action potential amplitudes (P = 0.017, CH = 29.4 ± 6.8 pps, AD = 23.5 ± 3.5 pps), were greater for children. MUAP_AMPS in relation with RT were similar between groups except the highest threshold MUs (RT = 28% MVC) were greater for the adults (1.02 ± 0.43 mV) than children (0.67 ± 0.24 mV) (P = 0.010).

Conclusions

Muscle activation and MU firing rates were greater for children, which likely indicated a greater operating point of MU control in comparison with adults during an isometric contraction performed at a relative submaximal intensity.

http://bit.ly/2S4FYn3

Treating open lower limb fractures successfully; thoughts and current practice on therapy and centralization in The Netherlands

Abstract

Introduction

The British Orthopedic Association (BOA) and British Association of Plastic, Reconstructive and Aesthetic Surgeons (BAPRAS) updated the evidence-based guidelines for the treatment and care of open lower limb fractures (BOAST 4). Following this, a Dutch version has been developed. The main points are multidisciplinary care, planning, and treatment of these injuries. Early osteosynthesis (within 7–14 days) combined with soft-tissue coverage results in more efficient care and less complications.

Aim

To study the variation in treatment and thoughts among trauma, orthopedic, and plastic surgeons.

Materials and methods

In this cross-sectional study 94 surgeons (57 trauma, 23 plastic, and 14 orthopedic surgeons) working at 46 centers completed an online questionnaire, consisting of 5 demographic, 14 hospital-related, 8 BOAST 4-related, and 2 centralization-related questions.

Results

There was a strong agreement among surgeons about the best moment for multidisciplinary consultation, which was before initial debridement, while in practice, this often does not occur. All surgeons agreed that the initial debridement should be performed immediately by any surgeon, but not solely by trainees. Plastic surgeons responded that the definitive stabilization and wound cover should not exceed 7 days, while half of the trauma and orthopedic surgeons agreed that it should not exceed 14 days. Finally, most surgeons agreed that Gustilo 3 fractures should be centralized. However, there was disagreement on the need for centralization of Gustilo 2 fractures.

Discussion

Surgeons agree on better and earlier multidisciplinary treatment of open lower limb fractures and the centralization of Gustilo 3 fractures.

http://bit.ly/2tn1z01

Normalisation of imprecise temporal expressions extracted from text

Abstract

Information extraction systems and techniques have been largely used to deal with the increasing amount of unstructured data available nowadays. Time is among the different kinds of information that may be extracted from such unstructured data sources, including text documents. However, the inability to correctly identify and extract temporal information from text makes it difficult to understand how the extracted events are organised in a chronological order. Furthermore, in many situations, the meaning of temporal expressions (timexes) is imprecise, such as in "less than 2 years" and "several weeks", and cannot be accurately normalised, leading to interpretation errors. Although there are some approaches that enable representing imprecise timexes, they are not designed to be applied to specific scenarios and difficult to generalise. This paper presents a novel methodology to analyse and normalise imprecise temporal expressions by representing temporal imprecision in the form of membership functions, based on human interpretation of time in two different languages (Portuguese and English). Each resulting model is a generalisation of probability distributions in the form of trapezoidal and hexagonal fuzzy membership functions. We use an adapted F1-score to guide the choice of the best models for each kind of imprecise timex and a weighted F1-score ( \(\hbox {\textit{F}1}_{3\mathrm{D}}\) ) as a complementary metric in order to identify relevant differences when comparing two normalisation models. We apply the proposed methodology for three distinct classes of imprecise timexes, and the resulting models give distinct insights in the way each kind of temporal expression is interpreted.

http://bit.ly/2STaTal

Disparity in online health information in pediatric vs. adult surgical conditions

Abstract

Background

Although the quality of online health information (OHI) for adult surgical conditions is well described, the availability of quality OHI for pediatric surgical conditions, and the comparison to that of adult surgical OHI, remains undefined.

Methods

Medical and lay terms for 15 pediatric and 15 adult surgical conditions were searched using Google in English. The Health on the Net Foundation, a non-governmental OHI accreditation body, designates approval for quality websites. We compared the role of patient population while controlling for disease incidence (pediatric vs. adult), term complexity (medical vs. lay), and order (earlier vs. later listing of websites) on availability of quality OHI among the first 100 websites for each term.

Results

Among the first 100 websites, the adjusted mean number of quality websites was 11.80 for pediatric vs. 17.92 for adult medical search terms, and 13.27 for pediatric vs. 18.20 for adult lay search terms (P < 0.05 for all). Term complexity did not affect quality, and earlier appearing results were more likely to be of high quality.

Conclusion

Availability of quality pediatric surgical OHI lags behind that of adult surgical OHI, even when controlling for disease incidence. These findings highlight the potential need for increased quality OHI in pediatric surgery.

http://bit.ly/2DGTisD

Proteomic and genomic profiling of pancreatic cancer

Abstract

Pancreatic cancer remains the most fatal human tumor type. The aggressive tumor biology coupled with the lack of early detection strategies and effective treatment are major reasons for the poor survival rate. Collaborative research efforts have been devoted to understand pancreatic cancer at the molecular level. Large-scale genomic studies have generated important insights into the genetic drivers of pancreatic cancer. In the post-genomic era, protein sequencing of tumor tissue, cell lines, pancreatic juice, and blood from patients with pancreatic cancer has provided a fundament for the development of new diagnostic and prognostic biomarkers. The integration of mass spectrometry and genomic sequencing strategies may help characterize protein identities and post-translational modifications that relate to a specific mutation. Consequently, proteomic and genomic techniques have become a compulsory requirement in modern medicine and health care. These types of proteogenomic studies may usher in a new era of precision diagnostics and treatment in patients with pancreatic cancer.

http://bit.ly/2Gr93Yn

Update on the Diagnosis and Management of Gastric Intestinal Metaplasia in the USA

Abstract

Gastric intestinal metaplasia (GIM) is a premalignant condition that can lead to intestinal-type gastric adenocarcinoma. It is characterized by a change in the gastric mucosa to a small-intestinal phenotype. Infection with Helicobacter pylori is the most common factor associated with GIM. Although GIM is typically a histologic diagnosis, various techniques have been developed to enable the endoscopic identification of GIM. There are presently no widely accepted guidelines on screening and surveillance strategies in patients with GIM in the USA. The aim of this review is to provide an update regarding the problem, diagnosis, and management of GIM in the USA.

http://bit.ly/2SNyIR1

What should professionals do for the parents of children with ADHD?

http://bit.ly/2S4b4Lz