Fetal Electrocardiogram Extraction and Analysis Using Adaptive Noise Cancellation and Wavelet Transformation Techniques

Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed.     

Effects of gender and age on esophageal biomechanical properties and sensation

OBJECTIVES: The effects of gender and age on human esophageal function is poorly defined. Our aim was to investigate the sensory perception and the biomechanical properties of the esophagus both at the smooth muscle and the striated muscle segments in age- and gender-matched healthy subjects. Eleven older individuals (five men and six women, aged 55-82 yr) and 11 younger healthy individuals (five male and six female, aged 22-45 yr) participated in this study. METHODS: Graded balloon distentions were performed at the striated muscle and the smooth muscle segments of the esophagus in a random order using impedance planimetry. Impedance planimetry facilitated simultaneous assessments of the biomechanical properties and sensory perception. RESULTS: We found that both at the striated and smooth muscle segments, the cross-sectional area, circumferential wall tension-strain relationship and the sensory thresholds were similar between men and women. In contrast, at both of these segments, the cross-sectional area was larger (p < 0.05), the circumferential wall tension-strain association had shifted significantly (p < 0.05) to the left (i.e., the wall was stiffer), and the median thresholds for discomfort and pain were higher (p < 0.05) in older subjects. The biomechanical properties and thresholds for sensory perception also varied between the two esophageal segments. CONCLUSIONS: Aging was associated with a larger lumen and a stiffer but less sensitive esophageal wall. Thus, aging but not gender may influence esophageal function.     

Acute severe asthma

Acute exacerbations of asthma are very common reasons for a presentation to emergency departments. This paper focuses on defining the high‐risk group, consideration of the concept of phenotypes of acute asthma, the assessment of severe and life‐threatening exacerbations and an emphasis on the management of the more severe end of the exacerbation severity. A number of evidence‐based guidelines exist throughout the world and are all slightly different. This reflects the poor evidence base for some of those recommendations. Thus, a large variation of treatment drugs, doses and regimen are used and clearly not standardised. This paper aims to present a summary of the best evidence and discuss some of these controversies. The most important aspect of treating an exacerbation of acute asthma is to review regularly and assess response to treatment. Severe and life‐threatening episodes should be treated with early use of intravenous treatment in a stepwise manner following the local guidelines. Non‐invasive ventilation and high flow nasal cannulae delivery of oxygen in the emergency department are evolving modalities, but evidence for their use is currently limited.     

The free healthcare initiative in Sierra Leone: Evaluating a health system reform, 2010‐2015

This article presents the findings of a theory‐based evaluation of the Sierra Leone Free Health Care Initiative (FHCI), using mixed methods. Analytical approaches included time‐series analysis of national survey data to examine mortality and morbidity trends, as well as modelling of impact using the Lives Saved Tool and expenditure trend analysis. We find that the FHCI responded to a clear need in Sierra Leone, was well designed to bring about needed changes in the health system to deliver services to the target beneficiaries, and did indeed bring funds and momentum to produce important systemic reforms. However, its ambition was also a risk, and weaknesses in implementation have been evident in a number of core areas, such as drugs supply. We conclude that the FHCI was one important factor contributing to improvements in coverage and equity of coverage of essential services for mothers and children. Modelled cost‐effectiveness is high—in the region of US$ 420 to US$ 444 per life year saved. The findings suggest that even—or perhaps especially—in a weak health system, a reform‐like fee removal, if tackled in a systematic way, can bring about important health system gains that benefit vulnerable groups in particular.     

Apolipoprotein E polymorphism in type 2 diabetic patients of Talca, Chile

Apolipoprotein E (apo E) modulates the metabolism of atherogenic lipoprotein particles and participates in the process of cellular incorporation of specific lipoproteins. Genetic polymorphism of apo E has been reported as an important dyslipidemia genetic marker associated with coronary artery disease. Type 2 diabetes mellitus is a disease with a high incidence and prevalence in the world. The main cause of death in these patients is myocardial stroke and a high incidence of general cardiovascular complications. The purpose of this work was to characterize the genotype of apo E in diabetic patients from Talca, Chile, in order to describe the allelic frequency of the apo E gene and its correlation to the lipids profile. Type 2 diabetic patients (200) were recruited from the Diabetes Program of Talca Hospital, Chile. Apo E genotype was determined by restriction fragment-length polymorphism analysis. A biochemical characterization was performed in all the subjects. Type 2 diabetic patients had elevated levels of glycemia, lipid profile and BMI compared to the control group. The E3/3 genotype and epsilon3 allele had a higher frequency in both groups. The E2/3 and E3/4 genotypes had higher levels of triglyceride (TG) and cholesterol respectively; however, there was not any statistical relationship between them. In conclusion, genotype of apo E in diabetic patients did not differ with healthy; E2/3 and E3/4 genotypes tend to have higher levels of triglyceride and cholesterol respectively. We think that these results corroborate that in the etiology of the dyslipidemia, there is more than one associate genetic marker.     

PDCD1 gene polymorphisms in different Mexican ethnic groups and their role in the susceptibility to hypersensitivity pneumonitis

ObjectiveHypersensitivity pneumonitis (HP) is an immunological disorder caused by antigen exposure in susceptible individuals. The PDCD1 polymorphisms, PD1.3 and PD1.5 have been associated with the susceptibility to inflammatory disorders. This study was conducted to test whether the PD1.3 and PD1.5 polymorphisms are associated with HP in Mexican patients and to explore the distribution of these polymorphisms in different Mexican ethnic groups.Design and methodsWe studied 98 Mexican patients with HP and 92 healthy Mexican controls. Also, 156 healthy Amerindian individuals from two ethnic groups were included (96 Mayans and 60 Mayos). Polymorphisms were determined by TaqMan 5′ nuclease assays.ResultsSignificant differences in the distribution of the PD1.3 and PD1.5 genotypes between HP patients and healthy Mestizo controls were not found. We observed a significantly different distribution of these polymorphisms in Mexican Mestizos when compared to the Amerindians.ConclusionsWe found no association between PD1 polymorphism and HP; however the distribution of these polymorphisms was different in Mexican Mestizos and Amerindians.     

Alloimmunization Against Well Defined Polymorphic Major Histocompatibility or Class I MHC Transfected L Cells Antigens Can Prevent Poly IC Induced Fetal Death in Mice

METHOD : It is possible to induce increased fetal resorption in a number of inbred murine matings by injecting Poly (I) Poly (C12U) 3.5 days postconception, a maneuver associated with natural killer-mediated damage to the feto placental unit such as occurs in spontaneous fetal resorptions. RESULTS : We show here that alloimmunization can block this effect. In addition, maternal immune responses induced by alloimmunization against isolated mutant class I or class II, as well as by immunization with class I MHC alloantigens (K^d) transfected L cells are sufficient to restore normal fetal viability. It is not necessary that the maternal immune response be specifically directed against paternal alloantigens fr the fetal protecton to ensue, since the effect occurs in inbred matings when the mother is immunized against unrelated class I or class II alloantigens. As in previous studies conducted in the murine species, not all MHC alloimmunizations are protective. In addition, as control, immunization with a monomorphic class I MHC molecular (37), transfected L cells, sheep red blood cells or hen egg lysozyme is without effect. CONCLUSION : These results indicate that defined MHC antigens can mediate fetal protection from induced fetal resorption, and suggest that one driving force in promoting MHC antigen polymorphism in mammals is their capacity to confer protection from NK mediated fetal demise.