Autoassociative MLP in Sleep Spindle Detection

Spindles are one of the most important short-lasting waveforms in sleep EEG. They are the hallmarks of the so-called Stage 2 sleep. Visual spindle scoring is a tedious workload, since there are often a thousand spindles in one all-night recording of some 8 hr. Automated methods for spindle detection typically use some form of fixed spindle amplitude threshold, which is poor with respect to inter-subject variability. In this work a spindle detection system allowing spindle detection without an amplitude threshold was developed. This system can be used for automatic decision making of whether or not a sleep spindle is present in the EEG at a certain point of time. An Autoassociative Multilayer Perceptron (A-MLP) network was employed for the decision making. A novel training procedure was developed to remove inconsistencies from the training data, which was found to improve the system performance significantly.     

Cognitive functions in relation to MRI findings 30 years after traumatic brain injury

OBJECTIVE: The aim of the study was to relate cognitive effects of a remote traumatic brain injury (TBI) to MRI findings and severity of injury. METHOD: Sixty-one patients were assessed on average 30 years after a TBI of variable severity. A comprehensive cognitive test battery was used to evaluate memory, executive functions and cognitive overall impairment. Multiple regression analyses were used to examine the relationships between cognitive variables and MRI volumetric findings (the volumes of the hippocampus and the lateral ventricles) and local contusions on MRI. Also, the effect of injury severity on cognitive outcome was evaluated. RESULTS: Reductions in hippocampal volumes and lateral ventricular enlargement were significantly associated with impaired memory functions, memory complaints and executive functions. Of the MRI parameters used, the best predictor for cognitive outcome was the volume of the lateral ventricle. There was only a modest relationship between severity of injury and cognitive performance. CONCLUSIONS: The results show that long-term memory impairments after TBI are associated with MRI volumetric measures. This suggests that the degree of diffuse injury leading to atrophic changes is prognostically more important than the initial severity of TBI.     

Parkinson’s disease: considerations for dental hygienists

Abstract: The prevalence of Parkinson’s disease (PD) is expected to double over the next 20 years owing to the increase in life expectancy. This progressive disease has several implications relating to oral health, and many are manageable with proper awareness and knowledge about the disease. This article reviews the epidemiology, pathophysiology, and characteristics of PD, as well as the treatments and oral health considerations to enable dental hygienists to undertake an informed approach to patient management strategies and provide optimal care.     

Reduction in length of stay for patients undergoing oesophageal and gastric resections with implementation of enhanced recovery packages

Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.     

Enhanced Bone Regeneration Using Porcine Small Intestinal Submucosa

Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material.     

阿克拉霉素A聚氰基丙烯酸异丁酯毫微粒冻干针剂体内外抗肝癌活性

阿克拉霉素A聚氰基丙烯酸异丁酯毫微粒的冻干针剂,能明显抑制体外培养人肝癌细胞株7703的生长,IC50为0.28μg·ml^-1。在0.8μg·ml^-1浓度时,克隆形成抑制率为90%,抑制作用有明显剂量依赖关系而未见明显时间依赖关系。静脉给药后,对常位移植人肝癌模型裸小鼠的抑瘤率为86.84%,肿瘤细胞增殖活性阳性率为20.83%。体内外均显示明显的抗肝癌活性,且体内抗肝癌活性比阿克拉霉素A冻干针剂强。