Continuous objective recording of fetal heart rate and fetal movements could reliably identify fetal compromise,which could reduce stillbirth rates by facilitating timely management

Stillbirth currently affects approximately 1 in every 200 pregnancies in the United Kingdom. Fetuses may exhibit signs of compromise as part of a stress response before stillbirth, including reduced fetal movements (RFM) and fetal heart rate (FHR) alterations. At present, and despite widespread use, current fetal monitoring is not associated with a reduction in perinatal mortality rate (PMR) as signs of fetal compromise are not adequately detected. This may be attributed to inaccuracies resulting from manual interpretation of results or subjective assessment of fetal activity. In addition, signs of compromise often occur only hours or days before fetal death, so may be missed by current monitoring methods, which are performed intermittently. A significant consideration is that correct identification of these signs and consequent intervention can result in the delivery of a healthy baby, thus preventing stillbirth. A hypothesis is presented, proposing prompt detection of fetal compromise with the use of 24-hour continuous objective fetal monitoring. With focus placed on obtaining long-term FHR and fetal movement data, prior interest has been found in developing devices for this purpose. However, introduction into clinical practice has not been achieved. Investigation of the hypothesis will begin with the design of a device to record the mentioned parameters, followed by an appropriate validation process. Should development and testing be successful, an eventual comparison in PMR with the use of continuous fetal monitoring vs current monitoring would address the hypothesis. It is suggested that a timely yet reliable indication of fetal wellbeing obtained via long-term monitoring would allow prompt and appropriate obstetric intervention and consequently reduce PMR.     

Protection of protease-activated receptor 2 mediated vasodilatation against angiotensin II-induced vascular dysfunction in mice

Background

Under conditions of cardiovascular dysfunction, protease-activated receptor 2 (PAR2) agonists maintain vasodilatation activity, which has been attributed to increased cyclooxygenase-2, nitric oxide synthase and calcium-activated potassium channel (SK3.1) activities. Protease-activated receptor 2 agonist mediated vasodilatation is unknown under conditions of dysfunction caused by angiotensin II. The main purpose of our study was to determine whether PAR2-induced vasodilatation of resistance arteries was attenuated by prolonged angiotensin II treatment in mice. We compared the vasodilatation of resistance-type arteries (mesenteric) from angiotensin II-treated PAR2 wild-type mice (WT) induced by PAR2 agonist 2-furoyl-LIGRLO-amide (2fly) to the responses obtained in controls (saline treatment). We also investigated arterial vasodilatation in angiotensin II-treated PAR2 deficient (PAR2^-/-) mice.

Results

2fly-induced relaxations of untreated arteries from angiotensin II-treated WT were not different than saline-treated WT. Treatment of arteries with nitric oxide synthase inhibitor and SK3.1 inhibitor (L-NAME + TRAM-34) blocked 2fly in angiotensin II-treated WT. Protein and mRNA expression of cyclooxygenase-1 and -2 were increased, and cyclooxygenase activity increased the sensitivity of arteries to 2fly in only angiotensin II-treated WT. These protective vasodilatation mechanisms were selective for 2fly compared with acetylcholine- and nitroprusside-induced relaxations which were attenuated by angiotensin II; PAR2^-/- were protected against this attenuation of nitroprusside.

Conclusions

PAR2-mediated vasodilatation of resistance type arteries is protected against the negative effects of angiotensin II-induced vascular dysfunction in mice. In conditions of endothelial dysfunction, angiotensin II induction of cyclooxygenases increases sensitivity to PAR2 agonist and the preserved vasodilatation mechanism involves activation of SK3.1.     

The burden of diabetes mellitus and impaired fasting glucose in an urban population of Sri Lanka

Aims

To describe the burden of diabetes mellitus and impaired fasting glucose in middle‐aged residents (35–64 years) in an urban area of Sri Lanka.

Methods

A cross‐sectional survey was conducted in the Ragama Medical Officer of Health area, from which 2986 participants (1349 men and 1637 women) were randomly selected from the electoral registry between January and December 2007. The participants underwent a physical examination and had their height, weight, waist and hip circumferences and blood pressure measured by trained personnel. Fasting blood samples were taken for measurement of glucose, HbA_1c and lipids. The prevalence of diabetes (fasting plasma glucose > 7 mmol/l) and impaired fasting glycaemia (fasting plasma glucose 5.6–6.9 mmol/l) and major predictors of diabetes in Sri Lanka were estimated from the population‐based data.

Results

Age‐adjusted prevalence of diabetes mellitus in this urban population was 20.3% in men and 19.8% in women. Through the present screening, 263 patients with diabetes and 1262 with impaired fasting glucose levels were identified. The prevalence of newly detected diabetes was 35.7% of all patients with diabetes. Among patients with diabetes, only 23.8% were optimally controlled. In the regression models, high BMI, high waist circumference, high blood pressure and hypercholesterolaemia increased the fasting plasma glucose concentration, independent of age, sex and a family history of diabetes.

Conclusions

Our data demonstrate the heavy burden of diabetes in this urban population. Short‐ and long‐term control strategies are required, not only for optimal therapy among those affected, but also for nationwide primary prevention of diabetes.     

VLSI circuits implementing computational models of neocortical circuits

This paper overviews the design and implementation of three neuromorphic integrated circuits developed for the COLAMN ("Novel Computing Architecture for Cognitive Systems based on the Laminar Microcircuitry of the Neocortex") project. The circuits are implemented in a standard 0.35μm CMOS technology and include spiking and bursting neuron models, and synapses with short-term (facilitating/depressing) and long-term (STDP and dopamine-modulated STDP) dynamics. They enable execution of complex nonlinear models in accelerated-time, as compared with biology, and with low power consumption. The neural dynamics are implemented using analogue circuit techniques, with digital asynchronous event-based input and output. The circuits provide configurable hardware blocks that can be used to simulate a variety of neural networks. The paper presents experimental results obtained from the fabricated devices, and discusses the advantages and disadvantages of the analogue circuit approach to computational neural modelling.     

Human Pose and Path Estimation from Aerial Video Using Dynamic Classifier Selection

We consider the problem of estimating human pose and trajectory by an aerial robot with a monocular camera in near real time. We present a preliminary solution whose distinguishing feature is a dynamic classifier selection architecture. In our solution, each video frame is corrected for perspective using projective transformation. Then, two alternative feature sets are used: (i) Histogram of Oriented Gradients (HOG) of the silhouette, (ii) Convolutional Neural Network (CNN) features of the RGB image. The features (HOG or CNN) are classified using a dynamic classifier. A class is defined as a pose-viewpoint pair, and a total of 64 classes are defined to represent a forward walking and turning gait sequence. Our solution provides three main advantages: (i) Classification is efficient due to dynamic selection (4-class vs. 64-class classification). (ii) Classification errors are confined to neighbors of the true viewpoints. (iii) The robust temporal relationship between poses is used to resolve the left-right ambiguities of human silhouettes. Experiments conducted on both fronto-parallel videos and aerial videos confirm our solution can achieve accurate pose and trajectory estimation for both scenarios. We found using HOG features provides higher accuracy than using CNN features. For example, applying the HOG-based variant of our scheme to the “walking on a figure 8-shaped path” dataset (1652 frames) achieved estimation accuracies of 99.6% for viewpoints and 96.2% for number of poses.     

An indentation apparatus for evaluating discomfort and pain thresholds in conjunction with mechanical properties of foot tissue in vivo

The mechanical properties of human foot tissue in vivo as well as discomfort and pain thresholds are important for various applications. In this study, an apparatus for measuring the discomfort and pain thresholds and the mechanical properties of human tissues is presented. The apparatus employs a stepper motor that controls the indentation speed, as well as a load cell and potentiometer that determine the corresponding reaction force and tissue deformation (displacement), respectively. A LabVIEW program (LabVIEW 8, National Instruments Corporation; Austin, Texas) was developed to control the indentation via a data acquisition card. The apparatus can accommodate indentor displacements up to 35 mm and can impart forces up to 150 N at a controlled indentation speed in the range of 0 to 10 mm/s. Tests showed that the displacement measurement error is <0.17 mm in the nominal range (0.5% in the full scale) and the measurement error of force is <1.6 N in the nominal range (1.1% in the full scale). Experimental results indicate that the apparatus is reliable and flexible for measuring the mechanical properties of foot tissue in vivo in conjunction with pain and discomfort thresholds.     

Care seeking in Sri Lanka: one possible explanation for low childhood mortality.

This paper examines care-seeking practices of mother caretakers with children less than five years of age in a rural district of Sri Lanka. The study was carried out from June to September 1998, documenting care-seeking practices of mother caretakers in a population of 2248 children in 60 villages. Of the five targeted diseases in the IMCI programme (Integrated Management of Childhood Illnesses) that were the focus of the study, acute respiratory infections (82.0%) and diarrhoea (14.8%) were predominant. Although malnutrition was highly prevalent it was not recognised by mother caretakers as an illness. Findings show that in 65.0% of illness episodes in children the mother caretakers sought outside care and treatment. Caretakers sought treatment from both private and public sectors with the majority seeking care in the private sector. Care seeking of mother caretakers was driven by symptomology. Young children with higher perceived severity and high-risk symptoms were brought to provider care more frequently, although a large percentage of episodes with low-risk symptoms were also brought for outside care. Care seeking was similar across socio-economic groups. The study points out that high care seeking of mother caretakers in Sri Lanka, particularly for illnesses with acute high-risk symptoms and signs, is a plausible explanation for the low level of childhood mortality despite the prevalence of a high rate of malnutrition.